Vitiligo is an autoimmune disease with a strong genetic component. It features areas of depigmented skin resulting from loss of epidermal melanocytes. Undoubtedly, genetic factors play key roles in this skin condition.
Is vitiligo hereditary?
Yes, vitiligo has a genetic basis. Nevertheless, less than half of those with the condition know of someone in their family who also has it. On the other hand, if you have it, it does not follow that your children will develop it.
What is the exact cause of vitiligo?
The exact cause of vitiligo is unknown. Some believe that it arises from genetic susceptibility activated by an environmental factor. It is like how an autoimmune disease occurs.
Vitiligo results in the destruction of skin pigment cells. Risk factors include a family history of the condition or other autoimmune diseases. Clearly, it is not contagious.
Vitiligo has two main types: segmental and non-segmental. As has been noted, most cases are non-segmental. In short, they affect both sides. Overall, in these cases, the affected area of the skin expands with time.
Likewise, about 10% of cases are segmental. In brief, they involve one side of the body. Ordinarily, in these cases, the affected area of the skin does not expand with time. Usually, tissue biopsy confirms diagnosis.
Genes and Vitiligo
By and large, genes are the instructions for life that make and run us. On the whole, one gene has the instructions to create one protein. And, each protein does a specific job in the body. For example, we have a gene that makes insulin that helps us use sugar. Similarly, there is one for hemoglobin that helps our bodies carry oxygen in the blood.
Experts compared the entire set of genes of groups of people with and without vitiligo. They found more than 10 genes associated with the condition. Some of these genes relate to the immune system, and some with melanocytes.
People who have it don’t have genes that other people don’t have. There is no vitiligo gene. These folks have different versions of these 10 genes that we all share.
Different versions mean different instructions, which means a different protein may get made. These different proteins may look or act different from those without vitiligo. And to some degree, these differences causes the destruction of melanocytes.
Lastly, it is important to mention that genetics is not the only one to blame for vitiligo. Environmental factors and chance each play a role as well. We know this because an identical twin of a person with the condition has a 23% risk of developing the disease even though most of their DNA is identical. If it’s all caused by genes, that risk would be 100 percent.