Did you know DNA influences your risk of varicose veins?
The genetics of lumpy veins
Do your legs ache or feel heavy at night? Do they cramp, burn or throb when you make sudden movements or when you stand for too long? What about your ankles, do they swell? If your answered ‘yes’ to all of these questions it’s time for a checkup, because you may be experiencing early symptoms of varicose veins. Veins are normally those faint lines you can see just under your skin, but if they start to bulge, twist like a cord and change colour, they’ve turned into varicose veins. If you start experiencing the symptoms mentioned above and happen to have a family history of varicose veins, you’d better brace yourself, because risk of varicose veins is largely inherited as a defect in the MTHFR gene.
Veins carry oxygen-deprived blood from your extremities back to your heart, and are designed with valves along their length to stop the blood from flowing backwards. For example, blood needs to be pumped against gravity in our legs, so contractions of the leg muscles pump blood up through the veins, and blood is kept flowing in a single direction – towards the heart – by closing of the leaflet valves. However, sometimes these valves stop closing properly, so blood can flow backwards and starts to collect in your veins. Varicose veins can just be a cosmetic problem, but for others they can be quite painful, especially if you need to stand for extended periods of time. Other less than pleasant symptoms of varicose veins include swelling, discolouration, skin conditions like eczema, and in severe cases they can even lead to ulcers, as well as bleeding.
Traditionally, severe cases of varicose veins were treated by vein stripping, which involved the surgical removal of affected veins, but several less invasive methods like sclerotherapy, a direct injection of medications that shrinks blood vessels, are available today. Advanced age, obesity, pregnancy, menopause and family history are all factors that can enhance ones risk for varicose veins.
The MTHFR gene makes an enzyme that controls the levels of homocysteine, a chemical involved in blood clotting. There are several different versions (genetic variants) of this gene, due to small changes in the DNA code. People who inherit two variants of MTHFR called rs1801131 and rs1801133, make much less enzyme compared to people with the normal version of the gene. Studies show that these individuals are also at higher risk for developing varicose veins. Interestingly, the clinical presentation of the disease seems to depend on the version of MTHFR that is inherited, with rs1801133 affecting veins along the trunk and rs1801131 affecting perforator veins that connect superficial veins to deep veins. People with both variants presented with trunk and perforator defects together.
Exactly how MTHFR variants contribute to the risk of varicose veins is unclear. It is possible that elevated homocysteine levels may damage the lining or the endothelium of blood vessels, but this is only a theory and further testing is required to substantiate it. Family history appears to be one of the best predictors of varicose veins, but there are several preventative measures that can be taken to reduce the risk of developing them. Since severe cases of varicose veins can affect quality of life, and in rare cases, even lead to blood clots, you will want to adopt preventative measures as early as possible to have the best chance of avoiding varicose veins.