SENTINEL WATCH October 30, 2006 Issue

YOUR NATURAL BIRTHRIGHT

RUTH WALKER

"Your daughter looks just like you!" the woman in the photo shop exclaimed with a big smile as she handed me the pictures she had just developed. I was pleased as punch to be connected with the delightful little girl she'd obviously noticed in my family snapshots, but I had to be straight with her: "She's not my daughter. She's my niece."

This exchange occurred several years ago. But it came to thought when I read a New York Times piece by Amy Harmon, "That Wild Streak? Maybe It Runs in the Family" (June 15, 2006). Both the article and the photo shop incident were reminders of the strong appeal, and hold, heredity can have. "A growing understanding of human genetics," wrote Ms. Harmon, "is prompting fresh consideration of how much control people have over who they are and how they act." The article reported that scientists are becoming more convinced that human behavior is influenced by specific genes. Not just diseases long considered hereditary, but propensities to conditions such as obesity and nicotine addiction, even character traits, are now traced to genetics.