Did you know DNA influences your risk of stretch marks?
Genes behind stretch marks and your risk of getting them
Tiger stripes, angel scratches or stretchies. Irrespective of what you choose to call them, many of us consider stretch marks undesirable. However, these long-held opinions are about to change. Fitness trainer Kayla Itsines displayed her stripes on Instagram. The online fashion retailer ASOS chose not to airbrush these imperfections from their swim suit models. Zinteta turned stretch marks into works of art. The way we perceive stretch marks is rapidly changing. We are finally being encouraged to accept our bodies with all its flaws, and recognize that 50-80% of us will develop stretch marks.
However, if you still insist on keeping these unseemly blemishes at bay, you should have a candid chat with your parents before you invest in cocoa butter or vitamin E oil. A study from the Journal of Investigative Dermatology found that genes can influence your predisposition to stretch marks. If you inherit a certain version of the tropoelastin (ELN) gene, it might be nearly impossible to avoid them.
Stretch marks (striae distensae) are tears that occur in the dermis layer of our skin. They tend to start off red or purple, and lose colour later as the cells die off. This process leaves areas of skin that are empty and soft to touch. Pregnancy is the worst culprit. However, bodybuilding, growth spurts, rapid weight changes and hormonal changes that trigger rapid stretching of the skin can also result in stretch marks.
Our skin retains its shape when stretched because of the dermis, the inner layer of our skin, made of collagen and elastin. Collagen gives our skin structure and strength, while elastin gives it elasticity. Elastin fibres are made of a protein called tropoelastin, and the instructions for making this protein are given by the ELN gene. Much of the elastin in our bodies is produced before birth or in the first few years of life. As we age, the amount of elastin we produce goes down drastically. In fact, only a minute amount of elastin is made by a middle-aged person. So it’s not surprising that scientists looking for genes linked to stretch marks identified ELN as a candidate gene.
Even though there are a few theories explaining why we might get stretch marks, the exact cause of these skin aberrations is not well understood. Researchers from the Eriksson lab were hoping genetic variants could explain why some of us get stretch marks while others don’t. Tung and colleagues analyzed DNA sequencing data from over 33,000 individuals. They found that the rs7787362 version of the ELN gene had the most significant association with stretch marks. It is thought that this form of the ELN gene affects the composition of the dermis, thereby increasing the risk of stretch marks.
Circumstances in life that bless us with stretch marks, like pregnancy or adolescent growth spurts, are noteworthy, even momentous. However, it’s only natural to be envious of the woman with absolutely no stretch marks, even after having twins. Scientists are hopeful that one day they will be able to treat stretch marks with technologies. Until then, we should get on board with Zinteta and embrace our stretch marks for the story they tell of who we are.