Tuesday, August 16, 2016

Lauren Treasure and Getting Started with DNA – #BYUFHGC

Lauren Treasure, product manager for AncestryDNA at BYU Conference Lauren Treasure, a product manager for AncestryDNA presented “Getting Started with DNA: Steps to Success” at the 2016 BYU Conference on Family History and Genealogy.

“Why take a DNA test?” she asked. To verify a family line. To supplement your existing research. To learn your ethnicity. (They try to show ethnicity from 1000 years back.) To break through a brick wall. To discover a story. To share a picture. And to connect with a cousin. Lauren told us that AncestryDNA currently takes six to eight weeks to post results of a test.

Lauren said we pass down several things from generation to generation. Besides things like names, stories, and heirlooms, we pass some of our DNA. You get exactly 50% from each parent. While the amount you get from each of your grandparents varies, it averages 25%. You don’t inherit the exact same DNA as your siblings. Your results can look different because the set of DNA you inherit is unique to you. That is why siblings’ ethnicity test results look a little different. She illustrated the point with these diagrams:

Ancestry DNA lettered blocks spell names and illustrate inheritance

Ancestry DNA simple chromosome diagram shows DNA inheritance

One of the results AncestryDNA gives you is an ethnicity estimate. To make the estimate they compare your DNA against 3,000 reference individuals from 26 different global regions.

AncestryDNA regions

They are always adding new regions.

She showed photos of some of the people in their reference panel.

Photos of persons in Ancestry DNA regerence panel

She showed a map with dots showing locations of reference panel individuals.

Map showing locations of persons in Ancestry DNA reference panel

A class member asked if you should be retested if you were tested a long time ago. Not unless AncestryDNA sends you a message. If you had your DNA tested on an old chip, then if they add a feature not supported on current chip they will let you know.

The other things AncestryDNA provides to those who take their DNA test is a list of matches to others who have taken the AncestryDNA test. These are sorted by closeness of the relationship. There is no limit to the number of matches. (I have 656.) One method of determining how closely you are related to another person is to measure how much DNA you share. She showed a chart from the ISOGG website showing on average much much DNA is shared by different relatives. Here’s a portion:

% shared Total centiMorgans shared half-identical (or better) Relationship
100% (Method I) 3400.00 Identical twins (monozygotic twins)
50% 3400.00 Parent/child
50% (Method I) 2550.00 Full siblings
25% 1700.00 Grandparent/grandchild, aunt-or-uncle/niece-or-nephew, half-siblings

(To see the complete chart, visit http://isogg.org/wiki/Autosomal_DNA_statistics.)

Another process of determining the relationship is measuring the number of meiosis events. In the chart below, if the number of meiosis events between two test takers and a common ancestor is 1 and 1, then the measurement is M2, which indicates siblings. If there are 5 events + 3 events = 8 events, that is 3rd cousins (M8).

Ancestry DNA meiosis event relationship example

  If you link your DNA to your tree, then AncestryDNA can show common ancestors between you and a DNA match.

Ancestry DNA Shared Ancestor Hint relationship chart

AncestryDNA looks back nine generations for shared ancestors. They call them hints for a reason; the shared ancestors might be someone else. Or one of the trees might be in error. A leaf next to the View Match button indicates there is a shared ancestor hint.

You can contact matches through the Ancestry anonymous messaging systems. AncestryDNA’s Anna Swayne sent a message to a DNA match, learned the story of an ancestor’s trip to America, and got a picture she hadn’t seen before.

Lauren talked about DNA Circles and New Ancestor Discoveries. See my article from last year, “Aaron Orr Talks Ancestry DNA at BYU Conference – #BYUFHGC.” She reminded us that not all DNA circles are on direct lines. There are other reasons you might share DNA. It could be because you match someone in the group, even though you are not descended from the person who is the subject of the circle.

While AncestryDNA tests are available in a wide number of countries (see “AncestryDNA In 29 Additional Countries” on my blog), AncestryDNA hasn’t yet translated all the materials into all the languages.

AncestryDNA has 2.2 million in their database now.

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