Once I got pregnant, my then husband and I became obsessed with whom our baby would resemble. So when Jason debuted at 7 pounds 3 ounces, with a shock of black hair, we were positive he'd inherited my family's average build and his dad's thick mane. Even so, he looked like he belonged to another couple -- an Inuit one, perhaps.
While you can't help but make predictions, you can never be sure what your little one will look like. "If we examined all a fetus's DNA, we still wouldn't be able to truly anticipate things," says Barry Starr, Ph.D., geneticist in residence at The Tech Museum, in San Jose, California. "So much is unknown about genes."
Even once Baby is in your arms and you've decided that he has your chin and Nana's eyes, you don't know how those features may change. Take my son, now 5. His face could be a clone of mine as a kid, and he's at the top of the growth chart (his dad is 6'6"). And that black hair? Totally blond.
Although his dad and I come from brown-haired stock, the code for Jason's light locks was etched in our DNA, says Samuel M. Scheiner, Ph.D., program director in the division of environmental biology at the National Science Foundation, in Washington, D.C. "When sperm met egg, the right mix of genes popped up so it could be expressed." Moreover, he explains, most traits are the result of multiple genes working together, so some of the effects of the genes are amplified, reduced, or completely turned off. No wonder it's so hard to know what kids will look like! Still, scientists do have some understanding about why we develop the features we do. This is your crash course in the ABCs of DNA.
AB Poll: 64% of readers would rather their baby look like them than Daddy!