The Lab Tour session was very interesting and included a demonstration on how DNA is extracted using a strawberry. The presenter then explained a little about the different tests available. Volunteers carrying colored circles were enlisted to demonstrate how mtDNA results are produced. Autosomal DNA lab analysis was explained in the same way, but this time the volunteers carried large cards with colored dots representing SNPs. Apparently the cards weren't correctly printed, so there was a lab failure as an audience member put it.
I didn't know that the Y DNA and mtDNA samples weren't analyzed using a chip? Only the autosomal testing is done with a chip. That's probably why the autosomal tests come back so quickly.
All of us are wishing for more accurate ethnicity results; but, as the presenter explained we are a long way from that goal at this time. As she stated all the DNA companies use different reference populations; which is the reason all the companies produce different results. For instance Family Tree DNA uses these data sets GeneByGene DNA customer database, Human Genome Diversity Project, International HapMap Project, Estonian Biocentre data. 23andme uses the Human Genome Diversity Project, International HapMap Project, and 1000 Genome Project. Ancestry uses the Human Genome Diversity Project and the Sorenson database. All of the companies use their own customer sample collections. So we don't get consistent results.
The presenter also shared a story about when she didn't follow lab procedures and temporarily blinded herself. That was in the early days of analysis when goggles were required so your eyes wouldn't be damaged by ultra violet light. The process is safer now. DNA and the Genealogical proof standard will be live streamed at 2:30 pacific time tomorrow. It's a free session.
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