When I began the process of having my DNA analyzed by 23andMe, I was mostly looking for surprises or things for which I had no expectations. The service does, however, provide an examination of how traits are linked to specific genetic markers. This ended up being more complicated and interesting than I anticipated.
The analysis could predict that I likely have blue eyes, which I do. The markers for hair straightness indicated I would have straighter hair than average, which isn’t the case in my actual expression. Wet earwax, no alcohol flush reaction, and bitter taste perception were traits that I could confirm as accurately predicted. It’s important to remember that expression does deviate from what DNA suggests for many reasons; broadly, epigenetic and nonheritable alterations are more important than we realize.
When I was in school, I was taught a myth about red hair. For many years it was assumed that it was caused by a single, regressive gene, which is not true. In fact, the analysis of my DNA did not give me increased odds of having red hair, or even whether I would have light or dark hair. It’s a reminder that we still know precious little about how our genetics influence our actual expression.
Having services like this one that can increase our genetic data greatly will lead to greater understanding over time and I’m glad I can contribute in a small way to the research going on behind the scenes.