Is it heritable? Twin study evidence suggests acne can be inherited

Have you ever wondered whether acne risk can be inherited?  Twin studies can shed light on this question.

In a previous post, I discussed twin studies which are the genetic gold standard to determine whether the liklihood of developing a given medical condition (or trait) is subject to heritable (i.e., genetic) influences.  The concept is fairly simple: Identical twins share essentially 100% of their genetic material while fraternal twins share 50%.  If genetics plays a strong role in risk for a disease, when twin pairs in which one member has the disease are studied, both twins will have the same disease in a larger percentage of the identical twin pairs as compared to the fraternal twin pairs. 

One study applied this concept to the study of acne.  The results were clear: in this study, approximately 80% of the degree to which acne severity varied was due to genetic effects. 

Although the underlying causative genes are not known, the fact that genetics plays such a large role in the development of acne suggests that future efforts to find the underlying genes are likely to reveal new drug targets.