July 16, AncestryDNA announced they reached the 1 million customer mark. This announcement came about a month following the announcement by 23andMe that they had genotyped 1 million customers. Unfortunately, AncestryDNA didn't accompany their announcement with a social media campaign similar to the 23andMe #Powerof1Million campaign, so no opportunity to examine the fine-scale pattern of customer growth at AncestryDNA. These two companies are clearly the "big hitters" in the direct-to-consumer genetic testing market, which is currently undergoing massive growth. The graphic below shows customer growth at 23andMe and AncestryDNA. The data for 23andMe is a bit richer due to collection of #Powerof1Million customer numbers and test dates, which fit nicely with company announcements while providing greater detail on the phases of growth. While it took 23andMe a bit over 7 years to reach 1 million, growth of the AncestryDNA database has been extremely rapid, reaching the 1 million mark in a little over 3 years and currently increasing at a much faster pace than 23andMe.
If finding relatives through DNA matching is a goal for doing a genetic test, the larger the size of the database, the greater the opportunity to identify a close match. However, composition of the customer database also plays an important role in determining the utility of genetic matches. For example, the 23andMe customer database is enriched with adoptees looking to connect with relatives. A recent story in the New York Times indicated that 6% of 23andMe customers are adoptees, whereas adoptees represent only 2% of the US population. Access to genetic tests also influences database composition. My wife's recent ancestry is essentially all Texas Germans that migrated in the later half of the 19th Century. Genetic tests on individuals from her family have many fewer close matches at AncestryDNA and 23andMe than tests on individuals from my family, which descend mostly from early American colonists and are broadly represented in the current US population. Currently, AncestryDNA and 23andMe customers are mostly in the US. Family Tree DNA has a much smaller database for its Family Finder test, but their customers represent a greater breadth of nationalities and they tend toward greater genealogical expertise, knowledge, and collaboration. Willingness and ease of sharing family history research and common genetic matches are important aspects for integrating genetic relationships into genealogical research.