23andMe V4 not compatible with some Autosomal Genetic Genealogy Tools!

I got several complaints that 23andMe doesn't work with some of genetic genealogy tools. So, I went ahead and investigated why. I then learnt about the new V4 chip from 23andMe. After reading several forum posts and my own personal investigation, I found the following: Even though 23andMe V4 has around 596869 SNPs, out of 714533 SNPs in Family Tree DNA, only 310690 SNPs matches (for Chr 1-22 and X). So, to compare a V4 with FTDNA one must assume 403843 SNPs as matching which will give very inaccurate results and thus making it incompatible for doing any reasonable autosomal comparison. This may be the reason why FTDNA does not allow V4 transfers into their database. Hence, I regret to say that 23andMe V4 will not be compatible with the below Genetic Genealogy tools for now.

Genetic Genealogy Tools affected:

• Autosomal Segment Analyzer
• Autosomal Compare
• Ancestral Cousin Marriages