Friday, November 22, 2013
Long awaited fix and update to 23andMe's Ancestry Composition any day now
Update 7/12/2013: 23andMe's Ancestry Composition is now better, but still not great
Almost a year ago, amidst great marketing fanfare and expectations from customers, 23andMe rolled out the Ancestry Composition (AC). This wasn't just supposed to be an updated Ancestry Painting (the company's previous main ancestry tool), but a state-of-the-art global and local ancestry deconvolution analysis that would put all competitors to shame.
Alas, not everything went according to plan.
For one, 23andMe's decision to represent Europe as ten ancestral regions, but not break up Sub-Saharan Africa or eastern Asia, was met with disbelief from many of the punters. Secondly, the AC suffered from an overfitting problem.
Overfitting happens when the individuals being tested are also used as reference samples, so they end up with inflated ancestry proportions based on their self-reported ancestry. For more info check out these threads at the 23andMe forums here and here. I was one of the overfitted customers, and it really pissed me off.
23andMe tried to fix the overfitting problem about six weeks after the launch, but that didn't go too well at all. See here.
Last week 23andMe announced that it would again attempt to fix the overfitting problem, and also break up Sub-Saharan Africa and eastern Asia into three and five regions, respectively. I'm not sure if the process has started yet, but you can get updates on how things are going here. You'll see these question marks next to the new reference sets in the AC until your updated ancestry proportions have been computed.
I was very excited about the AC when it was first announced, but now, after a year of waiting for the overfitting fix, I find the whole thing very underwhelming. I might, at some stage, write a review and user guide, but then again I might not.