Recent epidemiological studies have analyzed the link between vitiligo and new genetic factors.
What is Vitiligo?
Vitiligo is a skin disease characterized by the gradual and progressive appearance of white patches. These then tend to have a pejorative evolution over time, as they can also extend to the entire skin surface.
The pathology is characterized by a loss of pigment. In dermatology it is defined melanin and consists, in fact, in our natural color which establishes the phototype of the subject.
New epidemiological study
Recently an epidemiological study has led to the definition of new genetic bases of vitiligo.
A prevalence study found that anomalies in only 10 genes involved in the immune response are enough to cause vitiligo. In particular, in those that regulate gene expression and the function of T lymphocytes and key proteins in the body’s defense mechanism.
So this means that while in healthy subjects the immune response is a protective factor, in people who are affected by vitiligo this can cause an excessive increase in the aggressiveness of the cells of the immune system.
Therefore these alterations can contribute to causing the death of melanocytes along with other factors. Such as the imbalance of antioxidant capacities and the presence of a lipid structure susceptible to oxidative stress and able to influence the permeability of the cell membrane.
Further epidemiological studies
There is evidence from numerous studies that indicate the importance of genetic factors in the development of vitiligo. But it must be understood that these are very complex influences. Therefore epidemiological studies have shown that vitiligo, for example, tends to aggregate in families. However, this is not an absolute genetic risk.
Researchers have found that 20% of patients with vitiligo have at least one first-degree relative with vitiligo and that the relative risk of vitiligo for first-degree patients is increased by as much as 7 to 10 times.
And they also found that, for example, homozygous twins have a concordance rate of 23%, which also highlights the importance of environmental factors in the development of vitiligo.
Finally, large-scale genome-wide association studies were performed. They were conducted on both whites of European origin and on Chinese populations. And they even highlighted nearly 50 genetic loci that can configure the risk of vitiligo.
Many matching genes have therefore been identified. Several loci even have components of the innate and adaptive immune systems. They are also shared with other distinctive autoimmune loci and other multiple autoimmune diseases. Such as thyroid disease, type 1 diabetes and rheumatoid arthritis.
Finally, research has shown that the alteration of some loci that encode tyrosinase can be associated with vitiligo. Tyrosinase is encoded by the TYR gene.
It is an enzyme that essentially serves to activate the biosynthesis of melanin. It is also an important autoantigen in generalized vitiligo.
In conclusion, the researchers identified another gene also associated with vitiligo. It is the NAP1 gene. Specifically, it is a regulator of the innate immune system.
Proteina XB +1+1
Finally, again to complete the genetic studies of vitiligo, a research found that vitiligo is linked to a particular protein encoded as XB + 1 + 1.
It is a protein that plays a fundamental role in mitigating the protein response that we have just explained, namely the synthesis of melanin, and therefore in guiding the inflammation that is induced by stress in vivo.