This story is as intimate as I will get with you. In it, I unzip my genes and give you a sneak peek at my biological destiny. I took three DNA tests from three different DNA testing companies—one from a firm called Navigenics, one from 23andMe, and one from deCODE genetics.
I was so hyped up about getting my DNA analyzed, I didn’t really think about the consequences of having all that information at my fingertips. Perhaps that’s typical of a 25-year-old. I’m working at my first job out of college and living in New York City. There’s plenty in the here and now to worry about: The homeless man deliberately running into me on my way to work. Living on a shoestring budget. Finding Mr. Right.
Some of the test results from the three companies matched up with one another.
Some didn’t.
But I’m getting ahead of myself. Let me tell you what these tests actually test. Our DNA is made up of 3 billion base pairs, with myriad possible sequences of the four chemicals (represented as A, T, G, and C) that form the “instruction book” for a human being, geneticist Francis Collins explains. Sometimes a mistake gets introduced into the DNA sequence. Collins calls these mutations “misspellings”; when a large number of people share the same mutation, they’re known as single nucleotide polymorphisms (SNPs, pronounced “snips”). DNA testing companies use the SNPs to calculate people’s genetic risk of developing complex diseases. Broadly speaking, Navigenics, 23andMe, and deCODE genetics each say that they interpret genetic research gathered from scientific papers, apply it to a customer’s DNA sequence, and deliver the results online. The companies expect that most people will be interested in buying the test, everyone from the average joe to a college student to a politician to me—a half-Asian, half-European girl from Florida.
