Getting the Most Out of Your DNA Matches

Transcription

1 Helen V. Smith PG Dip Public Health, BMedLabSci, ADCLT, Dip. Fam. Hist. PLCGS 46 Kraft Road, Pallara, Qld, Website: Blog: Researcher, Author and Speaker ABN Getting the Most Out of Your DNA Matches Why do DNA Testing? Every living individual has a unique genetic identity. > 99.5% of DNA is shared between all humans, so tests examine areas that differ. The more DNA shared between two people, the closer the relationship between them. Comparing the DNA two people share predicts their likely relationship. There are different tests which can answer different questions. Currently the four tests: Y-DNA using the Y chromosome, mt-dna using mitochondrial DNA, Autosomal DNA using the 22 pairs of non-sex chromosomes (Ancestry, FamilyFinder FTDNA, MyHeritage) X-DNA using the X- chromosome (newest test to be utilised genealogically) DNA testing can be used for a number of purposes: it can examine the deep ancestry such as the Daughters of Eve from many thousands of years ago, it can give more recent ancestry around 500 years plus, it can help you determine genetic relatives ie cousins to about six to eight generations and it can be used to prove (or more often disprove) hypothesis we have from our traditional genealogical research. Be prepared! Sometimes it can bring to light family secrets, the adopted child, the non-paternal event or perhaps the sibling that is not a genetic sibling. DNA testing is just another tool. It is a good tool but must be used wisely. It is not able on its own, to give you names and show you a family tree, it may not always be able to answer the question of relatedness. You have to use it in conjunction with traditional research. Autosomal DNA Autosomal DNA (at-dna) is the newest test becoming available less than ten years ago and was greeted with great joy because both males and females could take this test. Autosomal DNA comprises the 22 pairs of non-sex chromosomes (so not the X or Y, remember males are XY and females are XX). As can be seen in the diagram they are named from They are traditionally arranged in size order (geneticists did this when looking for chromosome abnormalities). Chromosome 1 is the largest comprising around gene whilst chromosome 22 is the smallest at approximately 750 genes. at-dna: you inherit randomly from your mother and father and they inherited it from their parents etc. You inherit roughly 50% from each parent so about 25% from each grandparent, 12.5% from each greatgrandparent. The DNA can rearrange each transfer so even though your sibling also inherits 50% from your parents but will not be the same 50%! So siblings show different autosomal genetic pictures (except identical twins). This is very important as it also means that some DNA of your ancestors is lost in each generation. Both Helen V. Smith Page 1

2 my parents were only children so 50% of each of their parents was lost forever down my family line. My parents had to inherit the DNA to pass it on to me! (this is also why siblings can show quite different ethnicities) Another important concept is that you have a family tree that you can trace back using documents back many generations (if you are lucky and persistent in your research!). You also have a Genetic Family tree. Depending on the DNA test used this can be quite different in time. Y-DNA and mt-dna we have already seen can go back hundreds and even thousands of years because those types of DNA are inherited without recombination. With autosomal DNA, because of the recombination you are able, in general, to detect inheritable fragment back around 6-8 generations. Before that the fragment is so small that it might be a real inheritance from that ancestor or an arrangement that has occurred by chance. Now humans are biological systems so it is not as exact as that. You inherit 50% from each parent but you may have inherited 22% from your paternal grandmother and 28% from your paternal grandfather. Blaine Bettinger started the Shared cm project looking at the actual amounts inherited from known relatives and has produced a chart (which is attached to the handout) as you can see there is a range of cm inherited for known relatives. So for an Aunt/Uncle relationship the average cm would be expected to be 1744 while the project found there was a range of cM. This is a useful chart when looking at your matches. DNAPainter with Probability Chart and Shared cm chart This is a reason why at times the Genealogical databases say this person is a third cousin to you. Because they are simply looking at the amount of cm shared to determine a likely relationship. This does NOT mean it is the relationship. You also have to take into account blended families so that person may be a half third cousin as they are from a second marriage etc. Just as family relationships can be complicated so can the interpretation of DNA results! If you had a 1700cm match to you it is possible it is an Aunt or Uncle, they could also be a grandparent, a half-sibling or a double first cousin. Once you submit your DNA now is the time to make a bloodline tree, a direct ancestor tree at minimum with names dates and locations to upload to the testing site to help your matches determine any linkages. (In the event of sensitivities you could make your tree private on Ancestry). Attach the DNA test to the person in the tree who took the test. (can only attach a test to one tree) Watch any video resource the company may have about its test and the interpretation of results, how to navigate the website or use any of the tools on the website. Ancestry (You have received your results Now What?) (What to do with all those matches) (Possible relationships) (The search for Biological Family) (More Tips for identifying Biological Family) FTDNA (Introduction to Family Finder) (Family Tree DNA results explained) (FamilyFinder: Match Comparison) MyHeritage Helen V. Smith Page 2

3 (Understanding DNA Matching Technology) Literally hundreds of DNA videos on YouTube. Hooray now the results are back and you will already know a bit about the company s website and how to navigate it! Ancestry Click on DNA and this is the screen you get. Each of these you click into for further information. The first will give you Ancestry s determined ethnicities for you based on their algorithm and Ancestry s reference population. When you click through you will see some options. You can filter your search by relationship (the default) or by date (this does not show the relationships in date order but shows the matches in date order. You can filter by hints, new matches and by any matches you have starred. You can also search matches by surname (don t try Smith!) or by place all of which are helpful. When you look at your results use the note box to record information such as the believed common ancestor, the amount of DNA shared, the believed relationship AND any other shared matches and their cm shared. This means you don t have to click through to see the information. Helen V. Smith Page 3

4 You do this after you click on the match and get to the second page. To get the amount of cm in common click on the little i. Click on the pencil to add in the notes and they will show on the front screen. If you have the MedBetterDNA Chrome extension and are using Chrome as your browser you will be able to see the notes without needing to click on them. The Shared Matches tool is valuable as it shows who shares a match with you and with this kit and the shared match can at times, help you determine where the relationship might be. Just because it says there is no tree click through as the person may have a tree but not have attached their results to the tree. You have the option in your profile to provide extra information, this is a good place to have an external address and potentially also your Gedmatch number. Ancestry s messaging system appears to have flaws. I have found more success clicking through to someone s profile and then leaving a message rather than leaving one at the DNA page. But I would suggest trying the message through the DNA page link first because then the match can see the DNA match. There have been some issues when someone is only accessing their data on a mobile platform through the app. This has improved and it appears that they are seeing the messages. If the person does not have a subscription to Ancestry they will not see any trees attached to their matches but can contact the matches and receive messages from the matches. Ancestry has now due to privacy concerns and sadly some people not letting the person who took the test any access to their own results made it that each DNA test must be registered with a separate . With the person s permission you are still able to manage the kit. Go to the DNA page then click on settings (the little gear wheel on the right hand side of the page) This is where you will see a number of optional settings and where you are also able to download the raw DNA for potential upload to another site. Helen V. Smith Page 4

5 Further down that page is where you can invite some to view or perform another role on your DNA. You just need to click on Add a person fill in their and work out their role. Helen V. Smith Page 5

6 Family Tree DNA FTDNA, one login per kit usually. You can upload a family tree and is a good idea, again at least with the direct line ancestors. On the dashboard, top right side is my mitochrondrial results (Y-DNA results would also show here). On this page is where you can download your raw data to upload to a third party site like GedMatch. Click through to Matches and you get this. On the bottom of this page is where you can download a CSV file which lists all your matches with their s, match date, relationship shared cm and surnames of interest. Because I have had my mother tested and assigned her on my tree FTDNA are able to assign certain matches to the maternal bucket. My paternal matches are courtesy of a paternal First cousin once removed so FTDNA were able to assign those. It is worth filling in as much data as possible. Contact is directly via not via nay internal messaging system. Helen V. Smith Page 6

7 The mitochrondrial haplogroup automatically filled in if you have done the test with FTDNA. You have to fill in your earliest known ancestors and any ancestral surnames of interest. I do suggest filling in a place as well especially for common names. Knowing they are researching Smith is just not that helpful! FTDNA has a number of tools including filters such as In Common With and Not In Common With. You can see the match date, the expected relationship range based on the shared cm amount, the longest block, whether you have an X-DNA match or not any linked relationship and the surnames of interest. You can select up to five individuals to do further analysis. Then click the chromosome browser. On the top of the chromosome browser is where you can download an Excel/CSV file which has each match and where they match you on each of the 22 chromosomes and also on the X-DNA (assuming there is a match). This is the chromosome browser showing the matches of five people to me. These are matches of 5cM and above. The matrix tool is also valuable as it shows there if there is a relationship to each of the people to each other for up to ten people. Helen V. Smith Page 7

8 MyHeritage Click on View Matches Click on Review DNA match Helen V. Smith Page 8

9 MyHeritage will then show you shared matches between me and my mother and the amount DNA shared. They also show that we share a shared amount of DNA on the same chromosome (the symbol on the far right) Click on it and you get Show triangulated segments that are at least: (can choose a segment amount choose the 8cMs any less and you are running risk of a chance match). This now highlights the shared DNA on Chromosome 12 which is a 49.8cM segment. MyHeritage also has a chromosome browser so you can see on which chromosome you share DNA. Helen V. Smith Page 9

10 LivingDNA Currently (May 2018) Living DNA is not providing match details although this is expected to occur during What you will get is a detailed view of where they believe your ancestry is from. For me this worked out very well. As with all ethnicities results this depends on the companyy s testing algorithyms and their refernce populations. (currently German heritga eis reported as mid England due to the lack of a good German referemce popluation. This is being developed now). LivingDNA will also give you a mitochrondrial haplogroup and if you a amale also a YDNA haplogroup. These are both derived results and may not be as detailed as getting the specifi test done through FTDNA. My result was accurate. Helen V. Smith Page 10

11 Contacting That DNA Cousin I often get s that say: We are a DNA match tell me how we are related While I can understand someone finding a match and excitedly wanting to make contact, unfortunately, that is just not the best way to get someone willing to collaborate with you to determine the matching line. Especially when I have no idea at which company or third party site (like Gedmatch) you found the match, which kit (I currently administer nearly 20 kits for relatives and friends) the match was to or even what test. Those 20 kits all have autosomal and mitochondrial and Y-DNA done on a number of them. They are also at a mixture of Ancestry, FTDNA, 23andme and Gedmatch. (While in Ancestry you have to use their messaging system I have my address attached to my profile so that people can contact me directly). It is really important to think about what you write if you want the best response. You don t want to irritate your potential cousin before you even start. I will generally send a stock reply back explaining that I will need more detail before I can help them, at an absolute minimum the company they tested with, the type of test, the kit number/name they matched with and their kit number/name. Remember often our match is likely to be four or more generations back so telling me two surnames in your tree is not that useful. With larger families in the past siblings dispersed, so Yes you do have American, New Zealand, Canadian etc cousins plus people move today so could well be born in England and now just about anywhere! Ask nicely and be willing to collaborate! I don t have to spend time helping you and certainly won t for a request of we match, send me everything you have (don t laugh I have had requests like this!). At least some of your matches are likely to be adopted and may not know much. Also something to consider now is that many people are testing for the ethnicity results due to the advertisements and they are likely to be younger and also not family historians. We need to be careful to not overwhelm them with information and scare them off. A friendly message saying hi, that you saw Ancestry has said you were a match and from the size of the match guess it to be x generations back. Don t write War and Peace, be positive, say you are happy to help to find the link. Ask if they know their grandparent s names (people are less likely to worry about privacy if it is grandparents rather than parents you are asking about). Send off the message fairly soon after getting a match as the person may only log in to see their results and not log in again. People do have lives, have family emergencies, are not sure what to say etc and not everyone logs in every day to look at their results! Helen V. Smith Page 11