DNA - 101
KNOWLES SURNAME DNA PROJECT
UNDERSTANDING YOUR RESULTS:
mtDNA Haplogroups
(based on Facts & Genes article, Volume 3 , Issue 1)
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The Knowles Surname DNA Project can not benefit from and therefore does not use the mtDNA tests. However, some participants of the Knowles Project will no doubt decide to obtain an mtDNA test. Therefore, some basic information concerning the understanding of mtDNA test results will be provided here. Both males and females inherit mtDNA from their mother, and only the females pass on mtDNA. Your mtDNA represents your direct female line, which would be your mother, her mother, and so forth. Therefore, both males and females can take the mtDNA test, to learn about their direct female line. Your mtDNA can be traced back thousands or even 10's of thousands of years to a specific Haplogroup. Each mtDNA Haplogroup represents all those persons descended from one of the Clans, actually subdivisions from the female that we all descend from... In lay terms, the mtDNA Haplogroup is often referred to as the "Daughter of Eve" or the "Clan Mother". Each of these females or clan mothers now have millions of descendents today, who are all identified as belonging to the same Haplogroup, although their specific DNA signature may vary. Humans originated in Africa about 120,000 to 150,000 years ago. The original female to exist in Africa is known as the Mitochrondrial Eve. The "Clan Mothers" or "Daughters of Eve" are descendents of this original Mitochrondrial Eve. Scientists have identified a few dozen mtDNA Haplogroups around the world, and more mtDNA sub Haplogroups could be discovered as the scientists research remote populations. mtDNA Haplogroups are identified by letters of the alphabet, and some of these Haplogroup labels also have numbers. When a subgroup is identified a number is placed directly after the letter, for example J1 indicates that at least 1 specific subgroup for J has been identified. Below are some of the Haplogroups for mtDNA:
Each mtDNA Haplogroup originated in a different geographic area, thousands of years ago. For example, it is known that Haplogroup H originated in Europe, and was involved in a population expansion about 20,000 years ago. Over time, populations migrated, and Haplogroup H is now spread out over Europe, and about 40% of all Europeans belong to mtDNA Haplogroup H. Haplogroup U5 is the oldest European lineage, dating about 50,000 years ago, and may have come in contact with Neanderthals living in Europe at the time.
Your mtDNA represents your direct female line, which would be your mother, her mother, and so forth. Therefore, both males and females can take the mtDNA test, to learn about their direct female line. Your mtDNA can be traced back thousands of years to one of the original females. You Haplogroup defines which of these females was your ancestor. Your mtDNA Haplogroup will tell you some information about the general geographic area where you Daughter of Eve originated or at least where that Haplogroup is most commonly found today:
mtDNA Haplogroup X is found in Europe and Asia, and is believed to have migrated to the Americas about 15,000 years ago, making up a very small component of the Native American population. The mtDNA Haplogroup descriptions at Family Tree DNA provide additional information about your mtDNA Haplogroup. There are two mtDNA tests available from Family Tree DNA:
The test called mtDNA will test one region of mtDNA and provides the results for this region, and identify your Haplogroup. The mtDNA Plus test includes the mtDNA test, and also tests a second region of mtDNA. These regions are called HVR-1 and HVR-2, and are known as HV (Hyper Variable) Segment or HV Region. The HVR1 and 2 tests look at mutations with the control region of your mtDNA...an area of the mtDNA that is not known to 'code' for anything and enjoys the fastest mutation rate of any region in the mtDNA. The scientists use both the terms HV Segment and HV Region, and you may well find these terms used interchangeable, as well as the associated abbreviations. What is Tested:
Occasionally, an ancient human has been discovered and their mtDNA tested, such as the Ice Man. The 5,000 year old Ice Man belongs to Haplogroup K. The Cheddar Man belongs to Haplogroup U. The mtDNA test is often called an anthropology test, since mtDNA mutates very slowly, much more slowly than Short Tandem Repeats (STR's) that are tested with the Y-chromosome. The mtDNA test, besides telling you about your very distant direct female ancestor, can also be used to confirm genealogical relationships. If two persons are linked by a common female ancestor, then their results from the mtDNA test will match exactly. The two persons could be either male or female, as long as the male's mother belongs to the direct female line being tested. Since mtDNA mutates very slowly, if you are interested in finding matches to others, or using mtDNA for genealogy purposes, it is important to take the mtDNAPlus test. If you have already taken the mtDNA test (Maternal Match), this test can be upgraded to the mtDNA Plus test. The addition of testing the second mtDNA region, HVR-2, will shorten the time frame of any matches. It is highly recommended that the mtDNAPlus test be ordered by those persons interested in a genealogical application, or for matching. mtDNA has a very slow mutation rate. The time frame of the common ancestor for a random match is:
These time frames are for random matches. When you are utilizing mtDNA testing for genealogical purposes, you have identified the ancestors or potential ancestors, so the time frames shown above are not relevant. mtDNA test results show the Haplogroup, and the mutations compared to the standard, which is called the Cambridge Sequence (CRS). The CRS is simply the first mtDNA sequenced, so all the results are presented as the mutations compared to this standard. Since mtDNA mutates, or changes very slowly, the matching selection by Family Tree DNA only provides exact matches, since a partial matches are not genealogically relevant. Your mtDNA goes back much further than any written record. To order an mtDNA test from Family Tree DNA, click on the link below:
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A, B, C, D, F, G, H, I, J, K, L, L1,
L2, L3, T, U, V, X
The classification of mtDNA
Haplogroups should not be confused with the classification of Y-DNA Haplogroups.
Y-DNA and mtDNA each have a separate system for classifying the respective
Haplogroup. Y-DNA Haplogroups are based on a test of the Y-chromosome, and mtDNA
Haplogroups are based on a test of mtDNA. Even though Y-DNA has an A Haplogroup,
and mtDNA has an A Haplogroup, these Haplogroups are completely different.
Both
males and females inherit mtDNA, and only females pass on mtDNA.
