What Are Ancestry Gene Tests?
These are genealogical DNA tests which examine a person's DNA mutations and in so doing, can tell them something about their ancestors going back thousands of years. Making use of data compiled by anthropologists, the tests are only meant for curiosity purposes and do not for example determine diseases or genetic disorders. Instead they compare the person's DNA makeup with those of historic populations recorded on genealogical databases. Scientific studies indicate that we all had a common ancestor who lived in Africa up to 200,000 years ago. As those ancestors migrated out of Africa and across the rest of the world small genetic changes (mutations) occurred in their genes at different periods and locations. Many of those mutations have been recorded and are available for comparison. By comparing your own DNA you may be able to learn interesting facts about where your ancestors originated from and where they migrated. You may even discover if you are related to others with your family name. Occasionally the tests are used by those wishing to validate their eligibility for government grants or entitlements, such as Native American Rights. While genealogical testing will not provide an exact family tree it will help, depending on which type of test you take, to disprove or prove your family tree history research. It will also help to determine if 2 people are likely to descend from the same ancestor.
How Are Tests Carried Out?
Tests are most commonly purchased online from commercial labs. A collection kit is mailed to the consumer who will be required to collect a sample of cells via a painless cheek buccal swab. The swab is then returned to the lab for testing and a report is posted back normally within 4 to 8 weeks.
What Types Of Tests Are There?
(1) Ethnicity DNA Testing
This can be taken by men or women and will give an overview of their genetic makeup. A report will be returned with the estimated percentage of their ethnical makeup. Usually it is presented as a percentage of:
• European descendent: (European, Middle East and South Asian such as Indian or Pakistani).
• Sub-Saharan African descendents.
• East Asian descendent: Chinese, Korean, Japanese and Pacific Islands.
• Native American ancestry.
(2) Male Ancestor Testing - Y Chromosome Tests
Also known as the Y-Line DNA or Y DNA, this can only be used on men as the Y chromosome is only passed down from father to son. The chromosome contains tiny genetic markers called haplotypes that can distinguish one line of male descendents from another. If two men have shared markers they are likely to have had a male relative in common at some point in history. The exact degree of the relationship, i.e. how many generations ago is not possible to tell but rather is given within certain time frames. This type of test is often used by people with the same surname to know if they share a common relative in the distant past. It is also used to trace ancestry migratory patterns and linkage to specific ancestral groups. For example, many men express a desire to know if they have any Viking paternal ancestry (the Viking haplogroup). See also Y Chromosome DNA Tests.
(3) Female Ancestor Testing - mtDNA Tests.
This test can be used by both men and women and helps trace the maternal line. There are 33 major chartered female clans (or haplogroups) in the world and many of those clans are continent and even regional specific. According to geneticist Brian Sykes who wrote the popular book ‘The Seven Daughters of Eve’, 90 percent of Europeans are maternally related to 1 of 7 women. These women lived anywhere between 10,000 and 45,000 years ago and their offspring eventually went on to populate the whole continent. Sykes based his theory on research he carried out with mitochondrial DNA which only mutates every 10,000 years or so. While all human’s DNA is derived from thousands of ancestors, our mitochondrial DNA will always trace back to one branch of ancestry.
(4) Native American DNA Testing
These are female and male ancestor tests which specifically check for genetic markers associated with native Americans. This test can be a useful if no living relatives are native but characteristic traits are apparent or suspected.
What Are Genetic Markers?
These are genes or DNA sequences with known locations on a chromosome that can be used to identify haplogroups or clans. They are also used to identify certain genetic disorders. Labs can offer ancestry tests studying anywhere between 20 and 44 markers. The more markers checked, the more accurate the results. However the more markers examined, the more expensive the test.
Most Recent Common Ancestor
Most Recent Common Ancestor (MRCA) is a term often used in genealogical discussions. It is a statistic measurement of how long ago two individuals shared a common ancestor. The more markers tested, the more accurate and powerful the test. If you receive an MRCA rate of 14.5, this means the timeframe in which you and the other person shared a relative is between 0 and 14.5 generations ago. If it is 3.5, it is between 0 and 3.5 generations ago.
How Much Do Tests Cost?
Online or store purchased tests on average range between $150 and $300.
What Is The Genographic Project?
This project is a collaboration between IBM, the National Geographic Magazine, Family Tree DNA and the Waitt Family Foundation. The project’s aim is to collate huge amounts of DNA genetic material and use it to expand existing knowledge and map human population migration from its origins in Africa. The project is primarily focused on collating genetic material from indigenous people because their genetic markers have remained largely untouched for hundreds of generations. This will make it easier for scientists to study ancient migration patterns dating as far back as 150,000 years ago. Members are the public are invited to support the project by buying a Genographic Project Public Participation Kit and to submit their own buccal cheek swab. In return they will receive a personal report on their own ancestral migratory history. The results will be added anomalously to the projects database. Proceeds from the kit will be used to continue the works of the project. Kits costs $100 and can be shipped internationally.
Other Popular Genetic Tests
• Grandparent DNA testing
• Sibling DNA tests
• Twin DNA testing
• Genetic testing in pregnancy - to determine the chance that a mother is carrying a child with possible birth defects or genetic disorders.
• Genetic test for breast cancer - usually recommend to women with a history of this type of cancer in the family.
• Paternity testing - confirming who the father is!
• Genetic testing before pregnancy - These tests are normally carried out with the help of genetic advisors to determine the likelihood that parents will pass on any inherited genetic disorders.