Monday, March 5, 2018

RootsTech Living DNA and MyHeritage/36 Recombinations?

I watched RootsTech livestream. I bought a Living DNA kit after hearing their presentation. I was surprised the kit came only 2 days later. That was fast! I'm mailing the kit today March 4, 2018. I'm hoping I swabbed correctly? It said swab twice, but there was only one swab included? I'll review their results here on my blog when I get the results. 

The MyHeritage DNA 101: From Test to Results presentation at Rootstech was very interesting. The presenter said there are 36 recombination events per paternal and maternal sides of the 22 chromosomes; when our parents pass down their parents DNA to us. So if the first segment on a chromosome was given to you by a parent, which they got from their father, for instance, then a recombination event occurs and we switch to a segment from you parent's mother on the same chromosome. Another recombination can occur switching back to your parent's father's DNA.

I decided to count the recombination events representing the grandparents segments my parents passed down to me. I'm just curious if my segment attributions are correct? Recombination occurs an average of 1.5 times per chromosome according to the MyHeritage presenter. I found 4 recombination events on chromosome 1 on my maternal side. I may need to reexamine my matches on chromosome 1 on my maternal side? I still have many missing segments so I don't know how many recombination events have occurred? I'm thinking since an average of 1.5 recombination events occur per chromosome many of the smaller segments will be extended to fill out the chromosomes completely. I marked my chromosome chart below with the GF and GM for grandmother and grandfather. It does look like most chromosomes will have 1 or 2 recombination events, it's hard to say for sure with so many missing segments though? Recombination occurs more often on certain chromosomes and certain positions. I do see some chromosomes which may not have any recombination.


When you submit raw data from a different testing company MyHeritage has to take the data and infer missing data, since different companies test different positions. It may be a little better to test with them directly to get the most accurate results; although I've gotten very accurate results from them even though I transferred my raw data from another company.

MyHeritage also phases its results, like AncestryDNA. Phasing has a 1% error rate, resulting in breaks in long segments. They are able to stitch some of these together using an algorithm.

The new DNA testing companies such as MyHeritage and Living DNA have learned lessons from the companies that entered the market first. They have improved the layout of the information presented for easier reviewing of matches. MyHeritage has updated their chromosome browser to allow you to compare segments with multiple matches, something 23andMe first introduced. These companies have taken the best features of the early companies and added some even better features. They are also devising ways to make the results even more accurate. Better matching methods, ethnicity results, and easier reviewing of match data are going to far surpass results presented by the older testing companies. The older companies such as, AncestryDNA, need to step up their game to compete.

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