Diving Deeper Into Genetic Genealogy Handout

Presented by Melissa A. Johnson, CGSM [email protected]

ETHNICITY RESULTS testing has not been particularly useful for The ethnicity information (also known as genealogy, but tests are now more refined biogeographical data) that is part of a test and this is changing. taker’s overall DNA test results is based • STR (short tandem repeat) testing examines on comparisons of the test taker’s DNA to a specific number of STR markers (as chosen sample populations. Each of the DNA testing by the test taker—typically 12, 37, 67, or 111 companies uses different calculations to markers). Tests of 37 markers or more can compare the test taker’s DNA to proprietary be genealogically useful. sample populations, as well as to publicly available sample population data. As a result, With Y-chromosome STR testing, a test taker’s a test taker’s ethnicity information will vary Y-DNA matches are determined by the number from company to company. The science behind of identical STR marker values. Identifying ethnicity results is still in its infancy. Ethnicity how closely related a test taker is to his Y-DNA results can be interesting, but they are not as matches can be difficult, as a number of factors useful for genealogical research as examining need to be considered, including: DNA matches. • the number of non-matching STR marker values in relation to the number of markers tested; and Y-CHROMOSOME DNA TESTING • the mutation rates for the tested markers Y-chromosome DNA is passed down the male (some STR markers mutate at higher rates line, from father to son. The Y-chromosome than others). changes very little as it is passed from generation to generation. As a result, Family Tree DNA’s Y-chromosome match lists Y-chromosome DNA matches can be two men provide the number of non-matching STR who share a close relative such as a grandparent, marker values in terms of “genetic distance.” or two men who share a very distant ancestor For example, if two men are Y-chromosome who lived 2,000 or more years ago. Some very matches with exactly matching markers, small changes in the Y-chromosome take place FTDNA will show a genetic distance of zero. as it is passed from generation to generation. This can indicate that the two men have a These changes, known as mutations, can common ancestor within a “genealogical be extremely useful for solving genealogical time frame” (a time frame that is possible to problems and determining how closely related research). If two men who are Y-chromosome two Y-chromosome DNA matches are likely to matches show different values on two STR be. markers, FTDNA will show a genetic distance of 2. This typically indicates that the common Two types of Y-chromosome DNA testing is ancestor for these men is much farther back, available: and probably not within a genealogical time • SNP (single nucleotide polymorphism) frame. testing identifies the test taker’s deep ancestry and haplogroup. In the past, this To determine how long ago (in years or

© 2019 Melissa A. Johnson, CG | [email protected] DIVING DEEPER INTO GENETIC GENEALOGY generations) the common ancestor of two database where test takers can upload Y-DNA matches may have lived, see: https:// their data. This resource offers the ability isogg.org/wiki/Most_recent_common_ancestor. to connect with test takers from different companies. PRACTICAL TIPS FOR Y-DNA TESTING • Y-DNA or Surname Projects, where • Y-chromosome DNA testing can confirm groups of people come together to work on that two individuals share a common male identifying clusters of related individuals. ancestor, but the testing does not point • Y-DNA Tools (http://isogg.org/wiki/Y- to the specific identity of that ancestor. DNA_tools. However, Y-chromosome DNA testing • Y-DNA Mutation Rate Project (https:// alongn with other DNA tests and traditional thegeneticgenealogist.com/2017/05/05/the- genealogical research can prove the identity y-dna-mutation-rate-project/) of an ancestor. • A matching haplogroup for two males does not necessarily indicate a “Y-DNA match.” MITOCHONDRIAL DNA TESTING Some haplogroups are common to many Mitochondrial DNA (mtDNA) is passed from a individuals, such as R-M269, which is woman to her children, both male and female. common among European males. Whether However, only the woman’s female children will or not two individuals have a common male continue to pass the mitochondrial DNA on to line ancestor is determined by comparing their children; the woman’s male children will mutations. not pass it on. As with Y-chromosome DNA • Y-chromosome DNA testing is best testing, mitochondrial DNA changes very little used for problem-solving related to a as it is passed from generation to generation. specific question; unlike autosomal DNA, Y-chromosome DNA testing is not usually Mitochondrial DNA testing can include the useful for “fishing” for DNA matches. entire mitochondrial molecule (mtFull Sequence • A recommended testing plan is to test with test at FTDNA) or only two regions of the FTDNA on the Y-37 level first. If matches mitochondrial molecule, HVR1 and HVR2 appear to be relevant within a genealogical (mtDNA Plus test at FTDNA). The higher time frame, then the test can be upgraded level of testing (mtFull Sequence) is highly to Y-67 or Y-111 for further analysis. If test recommended. The lower level of testing takers do not have any relevant or close (mtDNA Plus) is not genealogically relevant. matches on the Y-37 level, there will be no benefit to upgrading the test. PRACTICAL TIPS FOR mtDNA TESTING • 23andMe does not offer Y-DNA SNP testing; • Mitochondrial DNA testing can confirm however, they provide test takers with a that two individuals share a common female predicted/estimated Y-DNA haplogroup. ancestor, but the testing does not point The 23andMe test can be used as a basis to the specific identity of that ancestor. for determining whether two people could However, mitochondrial DNA testing potentially be Y-chromosome DNA matches. combined with genealogical research and sometimes other test results can prove the USEFUL TOOLS identity of an ancestor. • A matching haplogroup for two females does • Y-Search (www.ysearch.org), a public not necessarily indicate a “mitochondrial

match.” Some haplogroups are common from all lines of his or her family tree. Siblings to many individuals from certain areas of do not inherit the same combinations from their the world. Whether or not two individuals parents, and as a result, will have some different have a common female line ancestor is autosomal DNA matches. determined by comparing the location and value of differences between two individuals. When a person takes an autosomal DNA • Mitochondrial DNA testing is best used test, the genetic testing company searches for for problem-solving related to a specific patterns within their DNA. If two people have question; unlike autosomal DNA, it is an identical pattern on the same section of the not usually useful for “fishing” for DNA same chromosome (a “segment”), those two matches. people are genetic matches to each other. This • 23andMe does not offer mitochondrial DNA means they share a common ancestor, from testing; however, they provide test takers whom they both inherited that identical DNA with their predicted/estimated mtDNA pattern. haplogroup. The 23andMe test can be used as a basis for determining whether two A matching segment between two people is people could potentially be mitochondrial measured in centimorgans (cM). Many genetic DNA matches. testing sites (both the testing companies and third party sites) provide testers with the amount of DNA they share with others (in AUTOSOMAL DNA TESTING centimorgans), and also identify on which Everyone has two copies of each of their twenty- chromosomes that DNA is shared. The three chromosomes—one copy inherited from predicted relationship between two individuals their mother, and one copy inherited from is based in part on the total amount of DNA their father. Of those twenty-three pairs of they share. chromosomes, one pair determines gender. The remaining twenty-two pairs are the autosomal USEFUL TOOLS chromosomes. Several tools are helpful for determining The autosomal DNA (atDNA) that each person relationships based on the amount of shared receives from his or her parents is passed DNA between two individuals: on from generation to generation through a • Autosomal DNA Statistics (https://isogg. process called recombination. When a child org/wiki/Autosomal_DNA_statistics) is conceived, the father’s two copies of a • Shared cM Project (https:// chromosome break and recombine, and then a thegeneticgenealogist.com/2017/08/26/ random half of that recombined chromosome august-2017-update-to-the-shared-cm- passes to the child as one of the child’s two project/) copies. The same recombination happens • GedMatch (www.gedmatch.com), a third with the mother, and the random half of her party tool allowing users from multiple recombined chromosome passes to the child testing companies to compare their DNA in as the other one of the child’s two copies. This one database. recombination happens for each of the twenty- two autosomal chromosomes. The result is that a child inherits autosomal DNA from ancestors

TESTING COMPANY COMPARISONS MyHeritage AncestryDNA • Chromosome browser • No chromosome browser • Internal messaging only • No X-DNA comparison available • Ability to view shared matches • Must send messages through Ancestry • Identifies if match is an X-DNA match • Ability to view shared matches (up to fourth • Many family trees cousins) • Higher match response • Matches filtered by parent (if parent tested) • Smaller database • High number of family trees • Accepts autosomal transfers • Family trees searchable by surname and location • DNA Circles, New Ancestry Discoveries, DNA MATCHES Genetic Communities (proprietary features) The key to using autosomal DNA in genealogy • Largest database is working with DNA matches. A test taker’s DNA matches are individuals with whom 23andMe the test taker shares matching segments of • Chromosome browser (can show segments autosomal DNA. In most cases, both individuals by ethnicity) inherited that segment from a shared ancestor • Must send messages through 23andMe (though in some cases, matches with a very • Most users are not public small amount of shared DNA can be “false • In some instances, must send users requests matches”). The amount of DNA shared between to share DNA information two individuals is an indicator of how far back • Matches filtered by parent (if parent tested) the most recent common ancestor may be. • Ability to view shared matches • Provides predicted paternal and maternal FISHING FOR MATCHES haplogroup information It is recommended that each person test with • Low number of family trees as many companies as possible, including • Mid-size database AncestryDNA, Family Tree DNA, 23andMe, • Health information (optional) and MyHeritage. Testing with the different companies provides you with the most DNA Family Tree DNA matches, as some people will have tested with • Chromosome browser only one or two companies. For example, if • User’s name and email address provided you have tested with 23andMe and Ancestry, • Ability to view shared matches but have not tested with Family Tree DNA or • Identifies if match is an X-DNA match uploaded your raw data there, you might miss • Ability to view whether match has taken out on a second cousin who has tested only Y-DNA or mitochondrial tests with FTDNA with Family Tree DNA. Getting your DNA into • Retains DNA samples for future use as many company and third-party databases as • Some family trees; difficult to navigate possible is extremely important. • Higher match response • Smaller database WHAT IS A RELEVANT MATCH? • Accepts autosomal transfers The most promising matches are those who are predicted to be more closely related to you, or

© 2019 Melissa A. Johnson, CG | [email protected] DIVING DEEPER INTO GENETIC GENEALOGY those with whom you share the most DNA (in ASKING OTHERS TO DNA TEST centimorgans). More distant matches can still Asking others to take a DNA test can be be promising, but it is more difficult to narrow challenging, even when it comes to approaching down the variety of possible relationship(s) relatives that you have known your whole between individuals who share smaller amounts life. Explaining the reason why the person’s of DNA. DNA would help you is a great start. If they understand that their DNA may help you WORKING WITH MATCHES: FIRST STEPS determine who your shared great-great-great- • View the match of interest’s online family grandfather is, they may be more open to tree, or ask the match to share their tree. testing. They may also be interested to know • Search for a common ancestor within your what they will get when they take the test match of interest’s family tree; if one can’t (for example, ethnicity estimates or health be found, look for common surnames or information that may be of interest to them). At common ancestral locations. the same time, they should be aware of some of • Identify the DNA matches that you and the risks of testing (finding relatives they didn’t your match of interest have in common; know they had, revealing long-hidden family determine if either you or the match can secrets, etc.), as mentioned in the previous identify a common ancestor with those lecture individuals. If a common ancestor can be determined, it is likely that you are related It can be even more difficult asking someone to your match of interest through that family that you don’t know very well to take a line. (There can be exceptions to this; for DNA test (perhaps someone who you’ve example, if your match is related to you on corresponded with but never met, or someone his or her maternal line, but is related to a that you are contacting because they are a known cousin of yours on his or her paternal descendant of an individual of interest). It often line.) helps to get to know the person, and let them • Pay attention to matches that you don’t have get to know you, prior to asking them to take in common with your match of interest. a DNA test. This can be done through sharing For example, depending on how close your family photos, developing a family tree for match of interest is, it may be possible to them, arranging an in person meeting, etc. In rule out some of your family lines as the instances such as this, it also helps to let the common line, perhaps based on the fact that person know why their DNA test would help the match of interest does not match your you, and them. first cousin (and should, in theory, given the match’s relationship to you). • Test known family members (such as TARGETED RESEARCH QUESTIONS parents, aunts, uncles, first and second Developing a targeted research question and cousins), and ask your matches to do the devising a plan to answer that question is the same. Looking at whether you have these key to using DNA test results as genealogical known individuals in common with your evidence. DNA alone cannot solve genealogical unknown matches will will help narrow problems; however, it can be used along with down how you may be related the unknown documentary evidence to do so. Targeted matches. testing plans are grounded in comparing the DNA of multiple people to determine how

© 2019 Melissa A. Johnson, CG | [email protected] DIVING DEEPER INTO GENETIC GENEALOGY they are related to each other and to identify their common ancestor. A testing plan may evolve as more people are tested, and as more information is discovered or additional hypotheses are created. DNA test results have the potential to provide relevant evidence, often that cannot be found elsewhere, in response to a targeted research question. Examples of research questions that could be answered partially using DNA evidence include: • Was Roman Kanetski or Edward Stasiewicz (or neither) the father of Walter Stasiewicz? • Where was Jozef Kujawski born and who were his parents? • Which of Jan Lipinski’s wives was the mother of his daughter Marianna? LEARNING MORE Bettinger, Blaine. A DNA Case Study Revealing a Misattributed Parentage Event with DNA. The Genetic Genealogist. https:// thegeneticgenealogist.com/2017/03/13/a-dna- case-study-revealing-a-misattributed-parentage- event-with-dna/)

______. The Family Tree Guide to DNA Testing and Genetic Genealogy. Blue Ash, Ohio: F+W Media, 2016.

Bettinger, Blaine T. and Debbie Parker Wayne. Genetic Genealogy in Practice. Arlington, Va.: National Genealogical Society, 2016.

Jones, Thomas W. Mastering Genealogical Proof. Arlington, Virginia: National Genealogical Society, 2013. (Errata: www. ngsgenealogy.org/galleries/Pubs_files/MGP_ ErrataAndCorrectedPages.pdf)

Wayne, Debbie Parker. Targeted Testing for Autosomal DNA. http://debbiewayne.com/pubs/ pub_NGSMag_201605_targeting.pdf