I have acne on my face and my husband doesn't. Is there any likelihood that our children will have acne?
-A curious adult from Nigeria The chances of your children having acne are higher because one of their parents has acne. A couple of studies have been done that show that acne, like lots of other traits, tends to run in families. In one study, it was found that many school-age boys with acne have a family history of acne. Does this mean it runs in the family? Not necessarily. Let's use an example to show how someone might be fooled by this finding. Imagine there is a family that lives near a toxic waste dump. The whole family has high rates of cancer. Is it because of their genes? Probably not. The cancer is probably the toxic waste dump's fault, not the family's genes. To try to figure out what role the environment plays, scientists often do a twin study. In a twin study, identical twins are compared to fraternal twins. If something happens more often in identical twins, then that something probably runs in the family. How does a twin study show something runs in a family? Remember, identical twins have exactly the same genes. Fraternal twins share only as many genes as any brother or sister. Because twins are born at the same time, the environment is as same as possible for them. So if something happens more often in identical than in fraternal twins, then it is most likely because they share the same genes. A twin study was done in 1995 that showed that identical twins were more likely to both have acne than fraternal twins. So, there are probably one or more genes involved in increasing your chances for acne. Even though scientists don't yet know what these genes are, it is clear from this study that acne runs in families. We'll have to wait for more studies to be able to predict how likely it is that your kids will get acne and what specific genes are involved.