Using your 23andMe data: exploring with MDS

Note: please read the the earlier post on this topic if you haven't. The above image is from 23andMe. It's from a feature which seems to have been marginalized a bit with their ancestry composition. Basically it is projecting 23andMe customers on a visualization of genetic variation from the HGDP data set. This is actually a rather informative sort of representation of variation. But there has always been an issue with the 23andMe representation: you are projected onto their invariant data set. In other words, you can't mix & match the populations so as to explore different relationships. The nature of the algorithm and representation produces strange results, so varying the population sets is often useful in smoking out the true shape of things. With the MDS feature I wrote about yesterday you can now compute positions with different weights of populations and mixes. This post will focus on how ...