Just to review, genes are the instructions for life that make and run us. Generally one gene has the instructions to make one protein. And each protein does a specific job in the body.So we have a gene that makes insulin that helps us use sugar. And one for hemoglobin that helps our bodies carry oxygen in the blood. And so on.Scientists compared the genomes (entire set of genes) of groups of people with and without vitiligo. They found more than 10 genes associated with vitiligo. As we might have guessed, some of these genes are involved in the immune system. And some with melanocytes.
It is important to mention that people with vitiligo don't have genes that other people don't have. There is no vitiligo gene. These folks just have different versions of these 10 genes that we all share.Different versions mean different instructions. Which means a slightly different protein may get made.These slightly different proteins may look or act differently than the ones made by people without vitiligo. And something about these differences causes the destruction of melanocytes.Let's discuss two of the identified genes and see how they might cause vitiligo. These two give a nice overview of how the immune system can get confused.MHC. The MHC (major histocompatibility) genes play an important role in the immune system. They label cells so the immune system can either pass by or attack.
People with vitiligo have a different version of the TYR gene. What scientists think is happening is that the immune system attacks the melanocytes because this TYR protein looks suspiciously like a red flag. A case of mistaken identity that leads to the destruction of melanocytes which leads to vitiligo.
So things can go wrong on either end. Sometimes a gene in an immune cell makes it attack the melanocyte. And sometimes a gene in the melanocyte makes the immune system attack it.Many of the other genes that scientists found act similarly. Some work in the immune system and others in melanocytes.