Have you taken a DNA test? Do you have questions on which DNA test to take or which testing company to use?
Would you like to break through those brick walls and locate descendants of your ancestors?
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DNA Testing Companies:
Note: Each testing company uses different algorithms to determine matches. In addition, ethnicity percentages are based upon their testing populations, so they will not match across testing companies. Therefore, your ethnicity percentages will change as each testing company acquires more testees!!!!
It is also important to understand DNA dies out over time....either due to disease or due to the fact that only half of a person's atDNA is passed to the next generation.
Remember, many people test to learn their admixture (ethnicity percentages) only! They are not interested in finding genetic relations.
Testing kits are now offered in 29 countries. Does not accept DNA transfers. Over five million customers have been tested as of September 2017.1 Testing is done via a saliva sample.
Excerpt from an article (link to article): Geneticists test about 700,000 single nucleotide polymorphisms (SNPs), or locations, on the genome to estimate ethnicity, said Crista Cowan, a corporate genealogist at Ancestry.com. To gauge accuracy, every one of the snips must meet a 98 percent quality measurement; otherwise, the sample must be resubmitted. DNA samples are then profiled against a "reference panel" of people from 26 regions encompassing nearly the entire world, she said.
Your DNA results are compared against 31 distinct populations worldwide. Neanderthal DNA can be identified. More than one million customers have been tested. Testing is done via a saliva sample.
FamilyTreeDNA - DNA Tests - this is the only company to offer mtDNA and YDNA tests.
Accepts transfers from 23andme Version 3 files and AncestryDNA only. 832, 294 customers have been tested as of 6 December 2016. Statistics on their tests can be found here. Testing kits are available worldwide. Testing is done via a cheek swab.
atDNA test results are generally returned in 4 - 6 weeks.
mtDNA test results are generally returned in 6 - 8 weeks.
Note: mtDNA test results completed prior to 24 Mar 2017 were updated to Build 17. Specifics are not known.
Y DNA test results are generally returned in 8 - 10 weeks.
Remember, each testing company provides their own analysis of your DNA results. If you have taking your atDNA test at each of the testing companies, the results will NOT match! They each have their own rules and testing populations!
For example, 23andme includes the X-chromosome in their cM calculations, whereas FTDNA does not.
|Matching Thresholds by Testing Company
||7 cM per segment AND 20cM overall
Living DNA - Cost: $159. Provides your DNA mix across 80 world regions, including 21 in Britain and Ireland. Test: cheek swab. Keep in mind, this is dependent upon their testing population from each of those regions!!! This site does not currently provide family matches but this will occur in the future.
Notes on GEDMatch:
Their tools do not use the same thresholds to determine matches!! For the One to One tool results to match the One to Many tool results, the One to One SNP threshold should be 500 and the cM threshold 5cM.
For males, matches on the X chromosome must be a maternal match.
If the user has not identified a gender for their kit, the following test can be done with 23andMe kits only:
Take a 23andMe kit for a female and compare it against a 23andMe kit for an unknown gender using the X one-to-one comparison tool, with the graphics bar turned on. If the color green is seen in the results, the kit with the unidentified gender is that of a female.
For example, Kit M085827 is for a female. Kit M202956 is unidentified. There is no color green in the X comparison performed, so therefore the gender of M202956 is male.
Notes on the Phasing tool:
It is in the blue 'Analyze Your Data' box under 'DNA Raw Data' - 7th bullet point. You need your kit and your one of your parents and it will produce two kit numbers for you, identifying which DNA you received from each parent. The P1 file (paternal) is the one you can use to find matches to your father. The M1 file (maternal) is the one you can use to find matches to your mother.
I have tested at both Ancestry and 23andme. I did this phasing test for both kits. I then ran my father's dna matching segment report and the matching segment report for both of the P1 phased kits (Ancestry and 23andme). I set the criteria for all 3 matching segment reports at 15cMs. My dad's kit matched to 13 kits other than my sister and I. My paternally phased kits matched on 5 of those 13 kits. While you're not catching everything, you are getting almost 50% of the matches. It might have been more if I had set the criteria to lower than 15cM.
Third Party Tool - DNAGedcom - Free but requires the user to register for a user ID and password. It offers downloads of DNA files from FTDNA and 23andme. It also offers tools for triangulation and ICW (in common with) segment comparisons of your matches. It has an Autosomal DNA Segment Analyzer as well.
Taken from Richard Hill's blog 7 Feb 2017:
The British breakdown is based on the Peoples of the British Isles Project of the University of Oxford. That study collected blood samples from 4,500 people in rural populations all over the UK. They focused on people whose parents and grandparents were all born in the same locality.
Some DNA Helpful Hints:
Information about European Haplogroups: Eupedia
Haplogroups - a group of individuals sharing a common ancestor; can denote the region the ancestor originated from (i.e. Western Europe, Middle East). There are 153 known haplogroups and subgroups.
For example, R-M269: R is the global positioning (large section of the world; Europe); M269 is the SNP, the location and time period (Western Europe/early Bronze Age).
SNPs - differences (or mutations) from the reference sequence
STRs - short tandem repeats - values in the YDNA
atDNA Genetic Distance - the number of mutations difference between yourself and your match
Mitochondrial DNA (mtDNA):
Mothers pass mtDNA to both sons and daughters. Can be traced back 10 generations or approximately 250 years. Only one family member should be tested; multiple family members need not be tested. Men and women can take this test.
Can provide health information.
mtDNA covers 16,569 bases, broken out as follows:
Hyper-Variable Region HVR2 - 1 - 576
Coding Region - 577 - 16,023
HVR1 - 16,024-16,569
A Full Mitochondrial Sequence test will analyze all 16,569 bases.
For more information, visit:
Mitomap - contains reports on mtDNA mutations.
Mitosearch.- Free from FTDNA; you can upload your raw DNA from FTDNA on this site. You need to set up a user ID and password. It allows users to search for mtDNA matches.
Fathers pass YDNA to their sons only. Can be traced back 10 generations, or approximately 250 years. Only one family member should be tested; multiple family members need not be tested.
Does not provide health information.
The 67 marker test is a good starting point. The greater the number of markers tested, the closer the relationships to be discovered.
Matches on this test with 3 or fewer differences (0-3 genetic distances) should be investigated to determine the connection.
Genetic distances are determined by the differences in the values of the markers. For example, marker 393 has a value of 12 for you and 13 for your match. The difference is 1. For marker 390, your value is 24 and your match's is 26. The difference is 2. The total of both differences is 3, or the genetic distance.
The standard reference sequence for DNA is the Cambridge Reference Sequence or CRS.
YDNA testing identifies haplogroups.
YDNA results may also be uploaded to YHRD or YSEARCH (this one is mostly for FTDNA customers).
The Y chromosome is 58 million base pairs long.2
Article on how to get the YDNA haplogroup from autosomal DNA for MALES ONLY.
Native American DNA:
95% of mtDNA lineages are in these haplogroups: A2, B2, C1b, C1c, C1d, D1 but these haplogroups are not EXCLUSIVE to Native Americans.
Marker D9S919, with a value of 9, is present in about 30% of Native American people and not known to be in any other ethnic group. Not having a value of 9 doesn't DISPROVE Native American heritage. The test for this is approx. $15 at FTDNA.
Native American males who were in America prior to contact with Indo-Europreans have haplogroups of C and Q3. The Y-DNA test can confirm a specific line is of Native American descent.
Autosomal DNA (atDNA):
Can be traced back 6 generations. Everyone should be tested. Can provide health information. Siblings do not inherit the same 50% of their parents' DNA.
Each individual inherits approx. 3,400 cM from each parent.
DNA can be obtained from hair or teeth. Molars are ideal but companies are not doing this type of work. Laboratories are expensive.
Transferring DNA Results:
atDNA can be transferred to FamilyTreeDNA for FREE from either AncestryDNA (Version 1 & 2) or from 23andme (Versions 3 & 4). A new kit number will be assigned. A fee of $19 is required to display your matches.
National Geographic DNA results can be transferred to FamilyTree DNA for free.
25 generations equals 1400 A.D. and 33 million ancestors!
Online videos and articles:
This is a great video about introductory DNA by Diahan Southard at a prior RootsTech conference and this is her handout.
This is a good video about the pros and cons of AncestryDNA testing.
Video entitled Using DNA to Identify Soldiers of the Western Front by Dr Maurice Gleeson 11 Sept 2016.
Video entitled How DNA Will Change the Face of Irish Genealogy by Dr Maurice Gleeson 5 Jun 2014.
Genetic Genealogy Ireland 2016 Conference: Videos posted here.
Video entitled Introduction to Molecular Genealogy.
ISOGG (International Society of Genetic Genealogy) is an excellent resource on DNA.
Future Genetic Genealogy Ireland presentations on YouTube.
Facebook's DNA Newbie Group (closed group - must click the Join button and the group's administrator will approve your request).
Third Party Sites:
DNAAdoption.com - Although developed for adoptees, this site can be used by anyone whiching to triangulate their atDNA matches.
DNA Land - An academic prodject with features for those whishing to upload their atDNA.
Pedigree Collapse: cousins marrying cousins - when there is a small pool of possible spouses
Chromosome Mapping/Triangulation - Allows users to narrow down the ancestral line shared between matches.
A mother can pass down a segment of DNA from either her father OR her mother, but not both for the same segment.
Under 5cM is only a true identical by descent match when ALL grandparents or great-grandparents have been tested.
1 See Dick Eastman, "Ancestry CEO Tim Sullivan Stepping Down; Will Transition to Chairman," Eastmans Online Genealogy Newsletter, posted 13 Sep 2017 (http://blog.eogn.com : accessed 13 Sep 2017).
2See Blaine T. Bettinger and Debbie Parker Wayne, Genetic Genealogy in Practice (Arlington, Va. : National Genealogy Society, 2016), 6, Y-Chromosome DNA (Y-DNA)