Thursday, 15 October 2009

The Camacho family

Posted by at

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)

The Camacho journey






Looking at the map highlighting the Camacho ancestors' route, the members of haplogroup R1b carry the following Y-chromosome markers:
M168 > M89 > M9 > M45 > M207 > M173 > M343

Today, roughly 70 percent of the men in southern England belong to Haplogroup R1b. In parts of Spain and Ireland, that number exceeds 90 percent.

What's a haplogroup, and why do geneticists concentrate on the Y chromosome in their search for markers? For that matter, what's a marker?

Each of us carries DNA that is a combination of genes passed from both our mother and father, giving us traits that range from eye color and height to athleticism and disease susceptibility.

One exception is the Y chromosome, which is passed directly from father to son, unchanged, from generation to generation. Unchanged, that is unless a mutation -- a random, naturally occurring, usually harmless change -- occurs.

The mutation, known as a marker, acts as a beacon; it can be mapped through generations because it will be passed down from the man in whom it occurred to his sons, their sons, and every male in his family for thousands of years. In some instances there may be more than one mutational event that defines a particular branch on the tree.

This means that any of these markers can be used to determine your particular haplogroup, since every individual who has one of these markers also has the others.

When geneticists identify such a marker, they try to figure out when it first occurred, and in which geographic region of the world. Each marker is essentially the beginning of a new lineage on the family tree of the human race.

Tracking the lineages provides a picture of how small tribes of modern humans in Africa tens of thousands of years ago diversified and spread to populate the world. A haplogroup is defined by a series of markers that are shared by other men who carry the same random mutations.

The markers trace the path your ancestors took as they moved out of Africa. It's difficult to know how many men worldwide belong to any particular haplogroup, or even how many haplogroups there are, because scientists simply don't have enough data yet.

One of the goals of the five-year Genographic Project is to build a large enough database of anthropological genetic data to answer some of these questions. To achieve this, project team members are traveling to all corners of the world to collect more than 100,000 DNA samples from indigenous populations.

The Camacho Ancestral Journey
Fast Facts:
• Time of Emergence: Roughly 50,000 years ago
• Place of Origin: Africa
• Climate: Temporary retreat of Ice Age; Africa moves from drought to warmer temperatures and moister conditions
• Estimated Number of Homo sapiens: Approximately 10,000
• Tools and Skills: Stone tools; earliest evidence of art and advanced conceptual skills

Skeletal and archaeological evidence suggest that anatomically modern humans evolved in Africa around 200,000 years ago, and began moving out of Africa to colonize the rest of the world around 60,000 years ago.

The man who gave rise to the first genetic marker in the Camacho lineage probably lived in northeast Africa in the region of the Rift Valley, perhaps in present-day Ethiopia, Kenya, or Tanzania, some 31,000 to 79,000 years ago. Scientists put the most likely date for when he lived at around 50,000 years ago.

His descendants became the only lineage to survive outside of Africa, making him the common ancestor of every non-African man living today.

But why would man have first ventured out of the familiar African hunting grounds and into unexplored lands? It is likely that a fluctuation in climate may have provided the impetus for the Hider ancestors' exodus out of Africa.

The African ice age was characterized by drought rather than by cold. It was around 50,000 years ago that the ice sheets of northern Europe began to melt, introducing a period of warmer temperatures and moister climate in Africa. Parts of the inhospitable Sahara briefly became habitable.

As the drought-ridden desert changed to a savanna, the animals hunted by these ancestors expanded their range and began moving through the newly emerging green corridor of grasslands. These nomadic ancestors followed the good weather and the animals they hunted, although the exact route they followed remains to be determined.

In addition to a favorable change in climate, around this same time there was a great leap forward in modern humans' intellectual capacity.

Many scientists believe that the emergence of language gave us a huge advantage over other early human species. Improved tools and weapons, the ability to plan ahead and cooperate with one another, and an increased capacity to exploit resources in ways we hadn't been able to earlier, all allowed modern humans to rapidly migrate to new territories, exploit new resources, and replace other hominids.

M89: Moving Through the Middle East
Fast Facts:
• Time of Emergence: 45,000 years ago
• Place: Northern Africa or the Middle East
• Climate: Middle East: Semiarid grass plains
• Estimated Number of Homo sapiens: Tens of thousands
• Tools and Skills: Stone, ivory, wood tools

The next male ancestor in the Camacho ancestral lineage is the man who gave rise to M89, a marker found in 90 to 95 percent of all non-Africans. This man was born around 45,000 years ago in northern Africa or the Middle East.

The first people to leave Africa likely followed a coastal route that eventually ended in Australia. These ancestors followed the expanding grasslands and plentiful game to the Middle East and beyond, and were part of the second great wave of migration out of Africa.

Beginning about 40,000 years ago, the climate shifted once again and became colder and more arid. Drought hit Africa and the grasslands reverted to desert, and for the next 20,000 years, the Saharan Gateway was effectively closed. With the desert impassable, these Hider ancestors had two options: remain in the Middle East, or move on. Retreat back to the home continent was not an option.

While many of the descendants of M89 remained in the Middle East, others continued to follow the great herds of buffalo, antelope, woolly mammoths, and other game through what is now modern-day Iran to the vast steppes of Central Asia.

These semiarid grass-covered plains formed an ancient "superhighway" stretching from eastern France to Korea. These ancestors, having migrated north out of Africa into the Middle East, then traveled both east and west along this Central Asian superhighway. A smaller group continued moving north from the Middle East to Anatolia and the Balkans, trading familiar grasslands for forests and high country.

M9: The Eurasian Clan Spreads Wide and Far
Fast Facts:
• Time of Emergence: 40,000 years ago
• Place: Iran or southern Central Asia
• Estimated Number of Homo sapiens: Tens of thousands
• Tools and Skills: Upper Paleolithic

The next Camacho ancestor, a man born around 40,000 years ago in Iran or southern Central Asia, gave rise to a genetic marker known as M9, which marked a new lineage diverging from the M89 Middle Eastern Clan.

His descendants spent the next 30,000 years populating much of the planet. This large lineage, known as the Eurasian Clan, dispersed gradually over thousands of years. Seasoned hunters followed the herds ever eastward, along the vast super highway of Eurasian steppe. Eventually their path was blocked by the massive mountain ranges of south Central Asia—the Hindu Kush, the Tian Shan, and the Himalayas.

The three mountain ranges meet in a region known as the "Pamir Knot," located in present-day Tajikistan. Here the tribes of hunters split into two groups. Some moved north into Central Asia, others moved south into what is now Pakistan and the Indian subcontinent. These different migration routes through the Pamir Knot region gave rise to separate lineages.

Most people native to the Northern Hemisphere trace their roots to the Eurasian Clan. Nearly all North Americans and East Asians are descended from the man described above, as are most Europeans and many Indians.

M45: The Journey Through Central Asia
Fast Facts:
• Time of Emergence: 35,000 years ago
• Place of Origin: Central Asia
• Climate: Glaciers expanding over much of Europe
• Estimated Number of Homo sapiens: Approximately 100,000
• Tools and Skills: Upper Paleolithic

The next marker of the Camacho genetic heritage, M45, arose around 35,000 years ago, in a man born in Central Asia. He was part of the M9 Eurasian Clan that had moved to the north of the mountainous Hindu Kush and onto the game-rich steppes of present-day Kazakhstan, Uzbekistan, and southern Siberia.

Although big game was plentiful, the environment on the Eurasian steppes became increasing hostile as the glaciers of the Ice Age began to expand once again. The reduction in rainfall may have induced desert like conditions on the southern steppes, forcing these ancestors to follow the herds of game north.

To exist in such harsh conditions, they learned to build portable animal-skin shelters and to create weaponry and hunting techniques that would prove successful against the much larger animals they encountered in the colder climates.

They compensated for the lack of stone they traditionally used to make weapons by developing smaller points and blades -- microliths -- that could be mounted to bone or wood handles and used effectively.

Their tool kit also included bone needles for sewing animal-skin clothing that would both keep them warm and allow them the range of movement needed to hunt the reindeer and mammoth that kept them fed.

These ancestors' resourcefulness and ability to adapt was critical to survival during the last ice age in Siberia, a region where no other hominid species is known to have lived.

The M45 Central Asian Clan gave rise to many more; the man who was its source is the common ancestor of most Europeans and nearly all Native American men.

M207: Leaving Central Asia
Fast Facts:
• Time of Emergence: 30,000 years ago
• Place of Origin: Central Asia
• Climate: Glaciers expanding over much of Europe and western Eurasia
• Estimated Number of Homo sapiens: Approximately 100,000
• Tools and Skills: Upper Paleolithic

After spending considerable time in Central Asia, refining skills to survive in harsh new conditions and exploit new resources, a group from the Central Asian Clan began to head west towards the European subcontinent.

An individual in this clan carried the new M207 mutation on his Y chromosome. His descendants ultimately split into two distinct groups, with one continuing onto the European subcontinent, and the other group turning south and eventually making it as far as India.

The Camacho lineage falls within the first haplogroup, R1, and gave rise to the first modern humans to move into Europe and eventually colonize the continent.

M173: Colonizing Europe—The First Modern Europeans
Fast Facts:
• Time of Emergence: Around 30,000 years ago
• Place: Central Asia
• Climate: Ice Age
• Estimated Number of Homo sapiens: Approximately 100,000
• Tools and Skills: Upper Paleolithic

As these ancestors continued to move west, a man born around 30,000 years ago in Central Asia gave rise to a lineage defined by the genetic marker M173. His descendants were part of the first large wave of humans to reach Europe.

During this period, the Eurasian steppelands extended from present-day Germany, and possibly France, to Korea and China. The climate fostered a land rich in resources and opened a window into Europe.

The Camacho ancestors' arrival in Europe heralded the end of the era of the Neandertals, a hominid species that inhabited Europe and parts of western Asia from about 29,000 to 230,000 years ago. Better communication skills, weapons, and resourcefulness probably enabled my ancestors to outcompete Neandertals for scarce resources.

This wave of migration into Western Europe marked the appearance and spread of what archaeologists call the Aurignacian culture.

The culture is distinguished by significant innovations in methods of manufacturing tools, more standardization of tools, and a broader set of tool types, such as end-scrapers for preparing animal skins and tools for woodworking.

In addition to stone, the first modern humans to reach Europe used bone, ivory, antler, and shells as part of their tool kit. Bracelets and pendants made of shells, teeth, ivory, and carved bone appear at many sites. Jewelry, often an indication of status, suggests a more complex social organization was beginning to develop.

The large number of archaeological sites found in Europe from around 30,000 years ago indicates that there was an increase in population size.

Around 20,000 years ago, the climate window shut again, and expanding ice sheets forced these ancestors to move south to Spain, Italy, and the Balkans. As the ice retreated and temperatures became warmer, beginning about 12,000 years ago, many descendants of M173 moved north again to repopulate places that had become inhospitable during the Ice Age.

Not surprisingly, today the number of descendants of the man who gave rise to marker M173 remains very high in Western Europe. It is particularly concentrated in northern France and the British Isles where it was carried by ancestors who had weathered the Ice Age in Spain.

M343: Direct Descendants of Cro-Magnon
Fast Facts:
• Time of Emergence: Around 30,000 years ago
• Place of Origin: Western Europe
• Climate: Ice sheets continuing to creep down Northern Europe
• Estimated Number of Homo sapiens:
• Tools and Skills: Upper Paleolithic

Around 30,000 years ago, a descendant of the clan making its way into Europe gave rise to marker M343, the defining marker of the Camacho R1b haplogroup. The Camacho Family are a direct descendent of the people who dominated the human expansion into Europe, the Cro-Magnon. The Cro-Magnon are responsible for the famous cave paintings found in southern France.

These spectacular paintings provide archaeological evidence that there was a sudden blossoming of artistic skills as these Cro-Magnon ancestors moved into Europe. Prior to this, artistic endeavors were mostly comprised of jewelry made of shell, bone, and ivory; primitive musical instruments; and stone carvings.

The cave paintings of the Cro-Magnon depict animals like bison, deer, rhinoceroses, and horses, and natural events important to Paleolithic life such as spring molting, hunting, and pregnancy. The paintings are far more intricate, detailed, and colorful than anything seen prior to this period.

These Camacho ancestors knew how to make woven clothing using the natural fibers of plants, and had relatively advanced tools of stone, bone, and ivory. Their jewelry, carvings, and intricate, colorful cave paintings bear witness to the Cro-Magnons' advanced culture during the last glacial age.

This is where Camacho genetic trail, as is known today, ends. However, as additional data are collected and analyzed, more will be learned about the history of the men and women who first populated the Earth.

-----------
Distribution of R1a (purple) and R1b (red) in Europe, Asia and North Africa
Pamphlet from National Geographic: "The Genographc Project: National Geographic Maps the Human Family Tree" -- front and back.

Notes: More information on the Genographic Project (2005-2010)

https://www3.nationalgeographic.com/genographic/. (All the information on this page was provided by genebase. The Genographic Map on the right, detailing R1a and the Camacho-ancestor-haplogroup-R1b (in red) proportions of today's population, is from Wikipedia.

It is noteworthy that scientists were suprised that all of humanity was rooted in Africa (they had originally assumed Asia). After it was known that Africa was the "cradle," scientists were next surprised that most of Europe was populated by persons who moved from Africa to Asia to Europe and not from Africa directly following the coastine of the Mediterranean. There is still debate over the origins of Modern Humans: Multiregional or Out of Africa (2001 article).

Dna test

Genealogical DNA test

From Wikipedia, the free encyclopedia

Jump to: navigation, search

A genealogical DNA test examines the nucleotides at specific locations on a person's DNA for genetic genealogy purposes. The test results are not meant to have any informative medical value and do not determine specific genetic diseases or disorders (see possible exceptions in Medical information below); they are intended only to give genealogical information. Genealogical DNA tests generally involve comparing the results of living individuals related to historic populations.

Contents

Procedure

The general procedure for taking a genealogical DNA test involves taking a painless cheek-scraping (also known as a buccal swab) at home and mailing the sample to a genetic genealogy laboratory for testing. Some laboratories use mouth wash or chewing gum instead of cheek swabs. Some laboratories, such as the Human Origins Genotyping Laboratory (HOGL) at the University of Arizona, offer to store DNA samples for ease of future testing. All United States laboratories will destroy the DNA sample upon request by the customer, guaranteeing that a sample is not available for further analysis.

Types of tests

The most popular ancestry tests are Y chromosome (Y-DNA) testing and mitochondrial DNA (mtDNA) testing. DNA tests for other purposes attempt for example to determine a person's comprehensive genetic history and/or ethnic origins.

Y chromosome (Y-DNA) testing

A man's patrilineal or fathers-line ancestry can be traced using the DNA on his Y chromosome (Y-DNA) through Y-STR testing, as follows: This is useful because the Y chromosome, like the patrilineal surname, passes down unchanged from father to son. A man's test results are compared to another man's results to determine the time frame in which the two individuals shared a most recent common ancestor or MRCA. If their test results are a perfect or nearly perfect match, they are related within genealogy's time frame.[1] Each person can then look at the other's fathers-line information, typically the names of each fathers-line ancestor and his spouse, together with the dates and places of their marriage and of both spouses' birth and death. This information table will be referred to again within the mtDNA testing section below as the (matrilineal) "information table". Here is an actual example of such an information table.[2] The two matched persons may find a common ancestor or MRCA, as well as whatever information the other already has about their joint patriline or fathers line prior to the MRCA -- which might be a big help to one of them.[3] Or if not, both keep trying to extend their fathers line even further back in time. Each may choose to have their test results included in their surname's "Surname DNA project". And each receives the other's contact information if the other chose to allow this -- thus they can correspond, and may even work together in the future.[4]

Women who wish to determine their paternal ancestry can ask their father, brother, paternal uncle, paternal grandfather, or a cousin who shares the same surname lineage (the same Y-DNA) to take a test for them.

What gets tested

Y-DNA testing involves looking at STR segments of DNA on the Y chromosome. The STR segments which are examined are referred to as genetic markers and occur in what is considered "junk" DNA.

STR markers

A chromosome contains sequences of repeating nucleotides known as short tandem repeats (STRs). The number of repetitions varies from one person to another and a particular number of repetitions is known as an allele of the marker. An STR on the Y chromosome is designated by a DYS number (DNA Y-chromosome Segment number). The example below shows the allele of Rumpelstiltskin's DYS393 marker is 12, also called the marker's "value." The value 12 means the DYS393 sequence of nucleotides is repeated 12 times—with a DNA sequence of (AGAT)12.

[edit] SNP markers

Strand 1 differs from strand 2 at a single base pair location (a C → T polymorphism).

A single nucleotide polymorphism (SNP) is a change to a single nucleotide in a DNA sequence. The relative mutation rate for an SNP is extremely low. This makes them ideal for marking the history of the human genetic tree. SNPs are named with a letter code and a number. The letter indicates the lab or research team that discovered the SNP. The number indicates the order in which it was discovered. For example M173 is the 173rd SNP documented by the Human Population Genetics Laboratory at Stanford University who uses the letter M.

Understanding test results

Y-DNA tests generally examine 10-67 STR markers on the Y chromosome but over 100 markers are available. STR test results provide the personal haplotype. SNP results indicate the haplogroup.

Haplotype

A Y-DNA haplotype is the numbered results of a genealogical Y-DNA test. Each allele value has a distinctive frequency within a population. For example, at DYS455, the results will show 8, 9, 10, 11 or 12 repeats, with 11 being most common[5]. For high marker tests the allele frequencies provide a signature for a surname lineage.

Kit Surname Haplo 3
9
3

 3
9
0

 1
9


 3
9
1

 3
8
5
a

 3
8
5
b

 4
2
6

 3
8
8

 4
3
9

 3
8
9
-
1		 3
9
2

 3
8
9
-
2		 4
5
8

 4
5
9
a

 4
5
9
b

 4
5
5

 4
5
4

 4
4
7

 4
3
7

 4
4
8

 4
4
9

 4
6
4
a

 4
6
4
b

 4
6
4
c

 4
6
4
d
11111 Rumpelstiltskin Q 12 23 13 10 16 17 12 12 13 14 14 31 18 8 9 11 11 27 13 19 28 14 14 15 15

The test results are then compared to another project member's results to determine the time frame in which the two people shared a most recent common ancestor (MRCA). If the two tests match on 37 markers, there is a 50% probability that the MRCA was fewer than 5 generations ago and a 90% probability that the MRCA was fewer than 17 generations ago.

Kit Surname Haplo 3
9
3

 3
9
0

 1
9


 3
9
1

 3
8
5
a

 3
8
5
b

 4
2
6

 3
8
8

 4
3
9

 3
8
9
-
1		 3
9
2

 3
8
9
-
2		 4
5
8

 4
5
9
a

 4
5
9
b

 4
5
5

 4
5
4

 4
4
7

 4
3
7

 4
4
8

 4
4
9

 4
6
4
a

 4
6
4
b

 4
6
4
c

 4
6
4
d
11111 Rumpelstiltskin Q 12 23 13 10 16 17 12 12 13 14 14 31 18 8 9 11 11 27 13 19 28 14 14 15 15
11178 Rumpelstiltskin Q 12 23 13 10 16 17 12 12 13 14 14 31 18 8 9 11 11 27 13 19 28 14 14 15 15

It is important to check the number of markers that will be tested before choosing a test. For example, the Genographic Project looks at only 12 markers, while most laboratories and surname projects recommend testing at least 25. The more markers that are tested, the more discriminating and powerful the results will be. A 12 marker STR test is usually not discriminating enough to provide conclusive results for a common surname.

STRs results may also indicate a likely haplogroup, though this can only be confirmed by specifically testing for that Haplogroups' single nucleotide polymorphisms (SNPs).

Haplogroup

Haplogroups are large groups of haplotypes that can be used to define genetic populations and are often geographically oriented.

Human Y-chromosome DNA (Y-DNA) haplogroups (by ethnic groups · famous haplotypes)

most recent common Y-ancestor
|

A
BT

|

B
CT

|

CF
DE

|
|

C
F
D E

|

G H
IJK

|

IJ K

|
|

I J
L M NOP S T

|

NO P

|
|

N O
Q R

























Y-DNA haplogroups are determined by SNP tests. SNPs are locations on the DNA where one nucleotide has "mutated" or "switched" to a different nucleotide. The nucleotide switch must occur in at least 1% of the population to be considered a useful SNP. If it occurs in less than 1% of the population, it is considered a personal SNP.

Haplogroup prediction

A person's haplogroup can often be inferred from their haplotype, but can be proven only with a Y-chromosome SNP tests (Y-SNP test). In addition, some companies offer sub-clade tests, such as for Haplogroup G. For example, Haplogroup G has a known modal haplotype:

DYS markers 3
8
5
a		 3
8
5
b		 3
8
8
 3
8
9
i		 3
8
9
ii		 3
9
0
 3
9
1
 3
9
2
 3
9
3
 3
9
4
 4
2
6
 4
3
7
 4
3
9
 4
4
7
 4
4
8
 4
4
9
 4
5
4
 4
5
5
 4
5
8
 4
5
9
a		 4
5
9
b		 4
6
4
a		 4
6
4
b		 4
6
4
c		 4
6
4
d
Haplogroup G: Modal STR values 14 14 12 12 29 22 10 11 14 15 11 16 11 23 21 31 11 11 16 9 9 12 13 13 14

Few haplotypes will exactly match the modal values for Haplogroup G. One can consult an allele frequency table to determine the likelihood of remaining in Haplogroup G based on the variations observed. Additional predictions include:

  • If DYS426 is 12 and DYS392 is 11, one is probably a member of haplogroup R1a1.
  • If DYS426 is 12 and DYS392 is not 11, one is probably a member of haplogroup R1b.
  • If DYS426 is 11, one is probably a member of haplogroup G,I, or J.
  • If DYS426 is 11 and DYS388 is 12, one is in the known modal haplotype for G shown above.

A Bayes classifier to predict the haplogroup probabilities for an observed haplotype is available on the web: Whit Athey Haplogroup Predictor.

Mitochondrial DNA (mtDNA) testing

Map of human migration out of Africa, according to Mitochondrial DNA. The numbers represent thousands of years before present time. The blue line represents the area covered in ice or tundra during the last great ice age. The North Pole is at the center. Africa, harboring the start of the migration, is at the top left and South America is at the far right.

A person's matrilineal or mothers-line ancestry can be traced using the DNA in his or her mitochondria, the mtDNA, as follows: This mtDNA is passed down by the mother unchanged, to all children. If a perfect match is found to another person's mtDNA test results one may find a common ancestor in the other relative's (matrilineal) "information table", similar to the patrilineal or Y-DNA testing case above. However, because mtDNA mutations are very rare, a nearly perfect match is not as helpful as it is for the above patrilineal case -- in the matrilineal case it takes a perfect match to be very helpful.[6]

Some people cite paternal mtDNA transmission as invalidating mtDNA testing[7], but this has not been found problematic here, in genealogical DNA testing, nor in scholarly population genetics studies -- see the rest of this article.

What gets tested

mtDNA by current conventions is divided into three regions. They are the coding region (00577-16023) and two Hyper Variable Regions (HVR1 [16024-16569], and HVR2 [00001-00576]).[8] All test results are compared to the mtDNA of a European in Haplogroup H2a2. This early sample is known as the Cambridge Reference Sequence (CRS). A list of single nucleotide polymorphisms (SNPs) is returned. The relatively few "mutations" or "transitions" that are found are then reported simply as differences from the CRS, such as in the examples just below.


The two most common mtDNA tests are a sequence of HVR1 and a sequence of both HVR1 and HVR2. Some mtDNA tests may only analyze a partial range in these regions. Some people are now choosing to have a full sequence performed, to maximize their genealogical help. The full sequence is still somewhat controversial because it may reveal medical information.

Understanding test results

The most basic of mtDNA tests will sequence Hyper Variable Region 1 (HVR1). HVR1 nucleotides are numbered 16024-16569.[9] Some test reports might omit the 16 prefix from HVR1 results, ie 519C and not 16519C.

Region HVR1 HVR2
Differences from CRS 111T,223T,259T,290T,319A,362C Not Tested

More extensive tests will also sequence Hyper Variable Region 2 (HVR2). HVR2 nucleotides are numbered 00001-00576.[10]

Region HVR1 HVR2
Differences from CRS 111T,223T,259T,290T,319A,362C 073G,146C,153G

[edit] Haplogroup

Most results include a prediction of mtDNA Haplogroup.

Human mitochondrial DNA (mtDNA) haplogroups

most recent common mt-ancestor

L0 L1 L2 L3
L4 L5 L6

M N
CZ D E G Q
A S
R
I W X Y
C Z B F R0
pre-JT P U
HV JT K
H V J T Former Clusters IWX

If you belong to a Haplogroup that is distantly related to the CRS, then the prediction may be sufficient. Some companies test for specific mutations in the coding region. For large Haplogroups, such as mtDNA Haplogroup H, an extended test is offered to assign a sub-clade.

Geographic origin tests

Autosomal tests that test the recombining chromosomes are available. These attempt to measure an individual's mixed geographic heritage by identifying particular markers, called ancestry informative markers or AIM, that are associated with populations of specific geographical areas. The tests' validity and reliability have been called into question but they continue to be popular. Anomalous findings most often result from databases too small to associate markers with all the areas where they occur in indigenous populations

Biogeographical ancestry

Autosomal DNA testing purports either to determine the "genetic percentages" of a person's ancestry from particular continents/regions or list the countries and "tribes" of origin on an overall basis. Admixture tests arrive at these percentages by examining SNPs, which are locations on the DNA where one nucleotide has "mutated" or "switched" to a different nucleotide. Tests listing geographical places of origin use alleles—individual and family variations on various chromosomes across the genome analyzed with the aid of population databases. As further detailed below, this latter type of test concentrates on standard identity markers such as the CODIS profile combined with databases like OmniPop, ENFSI and proprietary adaptations of published studies.

The admixture tests are designed to tell what percentages of Native American, "European", East Asian, and Sub-Saharan African ancestry a person has. One company[11] describes these four biogeographic groups as follows:

  • Native American: Populations that migrated from Asia to inhabit North, South and Central America.
  • European: European, Middle Eastern and South Asian populations from the Indian subcontinent, including India, Pakistan and Sri Lanka.
  • East Asian: Japanese, Chinese, Mongolian, Korean, Southeast Asian and Pacific Islander populations, including populations native to the Philippines.
  • African: Populations from Sub-Saharan Africa such as Nigeria and Congo region.

Based on customer feedback, the company in June 2007 introduced a new version of its EURO DNA test with a more limited range of countries that promises to have more meaningful clues to one's European ancestry. Both tests—the four-part ethnicity estimate and EURO DNA test—use a high number of so-called Ancestry Informative Markers whose genetic distance between populations reflects the populations' geographic distance from each other. The location and variation of these AIMs are proprietary to the company and have never been published.

In 2006, another company[12] developed an autosomal DNA ancestry-tracing product that combined the traditional CODIS markers used by law enforcement officers and the judicial system with OmniPop, a population database developed by San Diego detective Brian Burritt. Customers received matches to their profile's frequency of occurrence in world populations as well as a breakout for European ancestry based on the European Network of Forensic Science Institutes, or ENFSI [13]. As a public service, the company has supported the expansion of OmniPop, which currently encompasses over 360 populations, double that of its first release. The ENFSI calculator uses data from 24 European populations (5700 profiles). The two databases must be searched separately, because they are based on two different sets of markers. The company sells its product as the DNA Fingerprint Test. The 16 markers incorporated in its results are: D8S1179, D21S11, D7S820, CSFIPO, D3S1358, THO1, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, and FGA.

The theory behind using a forensic profile for ancestry tracing is that the alleles' respective frequency of occurrence develops over generations with equal input of the two parents since for each location we take one value from our mother and one from our father. It thus serves as a window into a person's total ancestral composition. The configuration of scores reflects inherited changes from all previous generations, all ancestral lines, and can predict an individual's unique probable ethnic matches based on the profile's commonness or rarity in different populations [14].

To give an idea of the inclusiveness of the latest version of OmniPop, the following are the last populations that have been added.

Greek, Sikkim (India), Bhutia (India), Italian, Argentinian (Misiones), Hungarian (E. Romani), Hungarian (Ashkenazim), Romanian (Szekler), Romanian (Csango), Tibet (Luoba).

As studies from more and more populations are included, the accuracy of results should improve, leading to a more informative picture of one's ancestry.

Along the same lines, yet another company[15] identifies the indigenous and diaspora populations in which an individual's autosomal STR profile is most common. This test examines autosomal STRs, which are locations on a chromosome where a pattern of two or more nucleotides is repeated and the repetitions are directly adjacent to each other. The populations in which the individual's profile is most common are identified and assigned a likelihood score. The individual's profile is assigned a likelihood of membership in each of thirty-four world regions:

  • Caucasian
    • European :
      • Eastern European: The Slavic speaking region of Eastern Europe.
      • Finno-Ugrian: The Uralic speaking region of Northeastern Europe.
      • Mediterranean: The Romance speaking region of Southwestern Europe.
      • Northwest European: The Celtic and Germanic speaking region of Northwestern Europe.
    • Near Eastern
      • Arabian: The Arabian Peninsula.
      • North African: Populations of the Atlas Mountains and Sahara Desert.
      • Mesopotamian: The historical “Cradle of Western Civilization” including modern Iran, Iraq and nearby territories.
      • Aegean: Anatolia region, modern territories of Southern Italy and Sicily, Greece, and Turkey.
      • Levantine: Populations along the coast of the eastern Mediterranean Sea.
  • Asian
    • Central and South Asian Regions:
      • Altaian
      • Eastern India
      • North India
      • South India
    • East Asian Regions:
      • Japanese
      • Malay Archipelago
      • North Chinese
      • South Chinese
      • Southeast Asian
      • Tibetan
  • Sub-Saharan African Regions:
    • East African
    • Southern African
    • West African
  • American Indians
    • Native North American Regions:
      • Arctic: Inuit (Eskimo) peoples of Alaska.
      • Athabaskan: Athabaskan speaking Dine peoples of western North America.
      • Mexican: Native peoples of Mexico, including the historical territories of the Aztec Empire.
      • North Amerindian: Native peoples of the Great Plains region of North America.
      • Ojibwa (East Algonquian): Eastern Algonquian speaking peoples of northeastern North America.
      • Salishan: Salish of the Pacific Northwest.
    • Native Central and South American Regions:
      • Amazonian
      • Andean
      • Central American
      • Mayan
      • Patagonian
  • Pacific Regions:
    • Australian: Aboriginal peoples of Australia and Papua New Guinea.
    • Polynesian

The STR analysis measures the frequency of a person's DNA profile within major world regions. Unlike SNP admixture tests, this analysis is based on objectively identified world regions and does not depend on any system of presumed biogeographic classifications. As most STR analysis examines markers chosen for their high intra-group variation, the utility of these particular STR markers to access inter-group relationships may be greatly diminished.

United States

Because of its history of immigration, slavery, and significant indigenous peoples, people of the United States have been interested in using genealogical DNA studies to help them learn more about their ancestry.

United States - Native American ancestry

Autosomal testing, Y-DNA, and mtDNA testing can be conducted to determine Amerindian ancestry. A mitochondrial Haplogroup determination test based on mutations in Hypervariable Region 1 and 2 may establish whether a person's direct female line belongs to one of the canonical Native American Haplogroups, A, B, C, D or X. If one's DNA belonged to one of those groups, the implication would be that he or she is, in whole or part, Native American.

As political entities, tribes have established their own requirements for membership, often based on at least one of a person's direct ancestors having been included on tribal-specific Native American censuses (or final rolls) prepared during treaty-making, relocation to reservations or apportionment of land in the late 1800s and early 1900s. One example is the Dawes Rolls. In addition, the U.S. government does not consider DNA as admissible evidence for enrollment in any federally recognized tribe or reception of benefits. Tribes are political constructs, not genetic populations.

Complicating factors in identification is recent evidence that indigenous North American Mitochondrial Haplogroups may not be limited to the five named.[citation needed] The vast majority of Native American individuals do belong to one of the five identified mtDNA Haplogroups. Many Americans are just discovering they have some percentage of Native ancestry. Some attempt to validate their heritage with the goal of gaining admittance into a tribe, but most tribes do not use DNA results in that way. These tests may be useful for adoptees to discover Native American ancestry.

United States - African ancestry

Y-DNA and mtDNA testing may be able to determine with which peoples in present-day African country a person shares a direct line of part of his or her ancestry, but patterns of historic migration and historical events cloud the tracing of ancestral groups. Testing company African Ancestry[16] maintains an "African Lineage Database" of African lineages from 30 countries and over 160 ethnic groups. Due to joint long histories in the US, approximately 30% of African American males have a European Y chromosome haplogroup[17] Approximately 58 percent of African Americans have the equivalent of one great-grandparent (12.5 percent) of European ancestry. Only about 5 percent have the equivalent of one great-grandparent of Native American ancestry. By the early 19th century, substantial families of Free Persons of Color had been established in the Chesapeake Bay area who were descended from people free during the colonial period; most of those have been documented as descended from white women (servant or free) and African men (servant, slave or free). Over time various groups married more within mixed-race, black or white communities.[18]

According to authorities like Salas, nearly three-quarters of the ancestors of African Americans taken in slavery came from regions of West Africa. The African-American movement to discover and identify with ancestral tribes has burgeoned since DNA testing became available. Often members of African-American churches take the test as groups. African Americans cannot easily trace their ancestry during the years of slavery through surname research, census and property records, and other traditional means. Genealogical DNA testing may provide a tie to regional African heritage.

United States - Melungeon testing

Main article: Melungeon#DNA testing

Melungeons are one of numerous multiracial groups in the United States with origins wrapped in myth. Historical research has documented that most such groups were descended from mixed-race people who were free in colonial Virginia and descended from unions between white women and African men. They moved to the frontiers of Virginia, North Carolina, Kentucky and Tennessee to gain some freedom from racial barriers.[19] Several efforts, including a number of ongoing studies, have examined the genetic makeup of families historically identified as Melungeon. Most results point primarily to a mixture of European and African, which is supported by historical documentation. Some people may have a very small amount of Native American lineages (none in one study). Though some companies provide additional Melungeon research materials with Y-DNA and mtDNA tests, any test will allow comparisons with the results of current and past Melungeon DNA studies.

General interest

Cohanim ancestry

Main article: Y-chromosomal Aaron

The Cohanim (or Kohanim) is a patrilineal priestly line of descent in Judaism. According to the Bible, the ancestor of the Cohanim is Aaron, brother of Moses. Many believe that descent from Aaron is verifiable with a Y-DNA test: the first published study of all in genealogical Y chromosome DNA testing found that very many of the Cohens did indeed have distinctively similar DNA, rather more so than general Jewish or Middle Eastern populations. These Cohens tended to belong to Haplogroup J, with Y-STR values clustered unusually closely around a haplotype known as the Cohen Modal Haplotype (CMH). This could indeed be consistent with a shared common ancestor, or with the hereditary priesthood having originally been founded from members of a single closely related clan.

But it should be noted that the original studies tested only six Y-STR markers, now considered a very low-resolution test. Such a test simply does not have the resolution to prove relatedness, nor to estimate reliably the time to a common ancestor. The Cohen Modal Haplotype (CMH), while notably frequent among Cohens, also appears in the general populations of haplogroups J1 and J2 with no particular link to the Cohen ancestry. So while many Cohens have haplotypes close to the CMH, a far larger number of such haplotypes worldwide belong to people with no likely Cohen connection at all. According to researchers (Hammer), it is only the CMH that is found in J1 that is to be attributed to the Aaron lineage, not the CMH in J2. It is not possible for Jews with the CMH in both J1 and J2 to all be descended from one man who lived approximately 3300 years ago, because J1 diverged from J2 10,000 years ago, significantly before the postulated time of Aaron.

There are a high percentage of Arabs in haplogroup J1 with the CMH: for example, 20% of men in Oman. There are also Arab men with one-step mutations from the CMH, such as Galilee Modal Haplotype and Negev Bedouin Haplotype (Coffman study 2005). Some of them claim a Cohen connection to the MCRA (most recent common ancestor) before Aaron, Abraham, who supposedly lived 500 years earlier than Aaron.[citation needed]

To some extent one could increase resolution by testing more than six Y-STR markers. For some this could certainly help to establish relatedness to particular recent Cohen clusters. For many it is likely that testing would still be unable to distinguish definitively shared Cohen ancestry from the more general population distribution. So far no openly published research indicates what extended Y-STR haplotype distributions appear to be characteristic of Cohens. Although some high-resolution testing has certainly been done, to date the results are held as closely guarded secrets. There have been no reports as to whether the high-resolution testing that has been done tends to confirm or call into question the basic hypothesis of a majority of Cohens' sharing a recent common ancestry back to a Y-chromosomal Aaron at an appropriate date. This is a fundamental problem with the "for-profit" DNA companies trying to sell their products: they have published no research proving their claims that the 37-marker test can prove relatedness to a mathematical degree of certainty within a genealogical time frame.

European testing

For people with European maternal ancestry, mtDNA tests are offered to determine which of eight European maternal "clans" the direct-line maternal ancestor belonged to. This is simply an mtDNA haplotype test based on the research in the book The Seven Daughters of Eve.

SNP testing may enable mostly European individuals to determine to which Sub-European population they belong:

  • Northern European subgroup (NOR) - mostly Northern and Southwestern European
  • Southeastern European (Mediterranean) subgroup (MED) - mostly Southeastern Europeans (Greeks or Turks)
  • Middle Eastern subgroup (MIDEAS) - mostly Middle Eastern
  • South Asian subgroup (SA) - mostly South Asian from the Indian sub-continent (i.e. Indian)

Hindu testing

The 49 established gotras are clans or families whose members trace their descent to a common ancestor, usually a sage of ancient times. The gotra proclaims a person's identity and a "gotraspeak" is required to be presented at Hindu ceremonies. People of the same gotra are not allowed to marry.

One company says it can use a 37-marker Y-DNA test to "verify genetic relatedness and historical gotra genealogies for Hindu and Buddhist engagements, marriages and business partnerships." This has not been supported by independent research. Any Y-DNA test can be used to compare results with another person whose gotra is known.

Benefits

Main article: Genetic genealogy

Genealogical DNA tests have become popular due to the ease of testing at home and the various additions they make to genealogical research. Genealogical DNA tests allow for an individual to determine with 99.9% certainty whether he or she is related to another person within a certain time frame, or with 100% certainty[citation needed] that he or she is not related. DNA tests are perceived as more scientific, conclusive and expeditious than research alternatives, although they are limited by restrictions on lines which may be studied.

The above results are theoretical and are the best case results. For example, the 12/12 marker test match gives a 50% likelihood in 7 generations. The probability is for the most recent common ancestor. [20] When having a 36 of 37 marker match, it gives a 90% likehood in eight generations.

Medical information

Though genealogical DNA tests results generally have no informative medical value and are not intended to determine genetic diseases or disorders, there has been a correlation established between a lack of DYS464 markers and infertility, and a correlation between mtDNA haplogroup H and protection from sepsis. Certain haplogroups have been linked to longevity.[22]

The testing of full mtDNA sequences is still somewhat controversial as it may reveal medical information. The field of linkage disequilibrium, unequal association of genetic disorders with a certain mitochondrial lineage, is in its infancy, but those mitochondrial mutations that have been linked are searchable in the genome database Mitomap[23]. The National Human Genome Research Institute operates the Genetic And Rare Disease Information Center[24] that can assist consumers in identifying an appropriate screening test and help locate a nearby medical center that offers such.

DNA in genealogy software

Some genealogy software programs now allow recording DNA marker test results, allowing for tracking of both Y-chromosome and Mitochrondrial DNA tests and results for relatives. Also DNA wall charts are available.