23andMe Chip Versions Comparison (ancestry only)

Illumina Global Screening Array Chip

Back on August 8, 2017, DTC personal genome service 23andMe quietly announced that it was upgrading its genotyping chip for a fifth time to the Illumina Infinium Global Screening Array-24 v1.0 Bead Chip (GSA) — aka 23andMe version 5 or v5 — and promised new customers more improved ethnicity reports, especially those with non-European ancestry, and those with African ancestry would be the first to receive more specific African ancestry updates. I'm excited already.

23andMe's latest chip upgrade comes on heels of the US Food & Drug Administration relaxing its restrictions on health testing for DTC personal genome companies. However it's unclear if customers on 23andMe's prior chips versions will be upgraded — and it may cost you. 

23andMe also has been notoriously slow with past major upgrades — the transition to 23andMe's revamped site took more than 2 years — so I jumped at the chance to test a third time (actually 4th) to be on the new promising v5 chip. 

Since I've 23andMe results from the two prior chip versions (v3 and v4), I can compare all three to determine if v5 lives up to the hype. You can read about all the bells and whistles of the GSA chip at genetic genealogist Debbie Cruwys Kennett's excellent blog here. My comparative analysis will focus mostly on ancestry features for 23andMe's last three chip versions (v3, v4, v5).  

At close of this deep dive I will reveal my new 23andMe v5 Ancestry Composition results and tell you whether it's worth testing NOW to be on the v5 chip. And if you're a current customer on an older chip version, I'll tell you if you should take a chance waiting on a future fee-based upgrade.

King Genome's Wisdom: 

• There are about 15 million known SNPs (aka Ancestry Informative Markers) for genetic ancestry but only 1-to-5 million are utilized by advanced genetic studies, and much less (~700,000) by vendors like DTC DNA testing companies (ie 23andMe). 

• According to ISOGG Wiki Chip Versions, here are the different microarray chip versions utilized by 23andMe for genotyping since the debut of its DTC personal genome service:
• v1: November 2007 
• v2: September 2008, ~555K SNPs (Illumina)
• v3: November 2010, >900K SNPs (Illumina OmniExpress)
• v4: November 2013, ~570K SNPs (Illumina OmniExpress)
• v5: August 2017, ~640K SNPs (Illumina Global Screening Array)