Anne Wojcicki is sitting in the kitchen of her California home, breast-feeding her third child, who gurgles happily throughout the conversation. The woman who set up 23andme and is worth a reported $440 million (£336 million), who was married to Google co-founder Sergey Brin and wore a white swimsuit to her wedding, and who is the sister of Susan Wojcicki, the chief executive officer of YouTube, obviously has good genes, but she’s more interested in yours.
Her £149 mail-order genetic-testing kit was one of the most popular Christmas presents of 2019. The kit can not only test for ancestry, revealing unexpected family members (in Wojcicki’s case, a cousin she didn’t know), but it is being used to help to treat diseases such as Parkinson’s and