Direct-to-consumer genetic tests don't necessarily give customers the full view of their genetic risks, a soon-to-be genetic counselor warns in an op-ed in the Los Angeles Times.
Sarah Hopkins, who is in her last semester of training to be a genetic counselor, notes that such testing only looks at a few genes. For instance, 23andMe's breast cancer risk test examines three mutations in the BRCA1 and BRCA2 genes, but Hopkins adds that there are many other genes — such as PALB2, CHEK2, and PTEN, among others — in which variants can boost breast cancer risk.
She argues that incompleteness like this contributed to the US Food and Drug Administration's decision in 2013 to prevent 23andMe from selling its health risk test. FDA has since relented, and 23andMe now offers a scaled-down version of its health test. The BRCA report got the OK earlier this year. She also notes that these results come without the guidance of a genetic counselor.
Hopkins, who knows she harbors a BRCA2 mutation based on testing after being diagnosed with bilateral breast cancer, underwent 23andMe testing, and her results indicated that no variants were found in BRCA1 or BRCA2. "I felt a flicker of elation, until I remembered that it was incorrect," she writes.