Pregnancy or rapid changes in weight can lead to stretch marks, but your genetics play a vital role in whether you see those lines across your skin.
The Genetics of Stretch Marks
23andMe scientists have identified 544 genetic variants associated with stretch marks.
As part of 23andMe’s regular cadence of releasing new trait reports, 23andMe now offers a report on a customer’s genetic predisposition toward having stretch marks, also known as striae distensae.
The new report analyzes a customer’s genetic data against those variants we have identified. It takes into account a customer’s age, sex, and ancestry and reports back whether that customer is more or less likely to have stretch marks.
Not Just Genetics
Some of us are more susceptible to stretch marks than others because of environment, age, and sex, but genetics also plays an important role.
Studies have shown that skin cells from people with stretch marks have lower amounts of specific proteins that are important for skin elasticity and repair. So when this skin is stretched rapidly from, say, pregnancy or weight loss or gain, the damage may be repaired, but it can also leave behind marks.
More than five years ago, 23andMe published a first-of-its-kind study looking at the genetics behind stretch marks, identifying an association near the gene that encodes for the elastin protein.
The new Stretch Marks trait report and the now more than two-dozen other trait reports we offer within the Health + Ancestry Service are meant to give customers a bit more insight into genetics. They also add to the understanding of how your DNA and environment interact to help influence all the many things that are part of who you are.