Which mutation has been associated with an increased risk of multiple sclerosis?

The association of multiple sclerosis (MS) with the HLA-DRB1 allele is well-documented in epidemiological studies. This gene encodes a protein that is part of the major histocompatibility complex (MHC), which plays a crucial role in the immune system by presenting peptide antigens to T cells. Variants of the HLA-DRB1 gene, particularly certain alleles, have been identified to significantly increase the susceptibility to MS. The risk conferred by these alleles indicates not only a genetic predisposition but also highlights the importance of autoimmune mechanisms in the pathogenesis of multiple sclerosis.

Mutations or variations in other genes such as the TGF-beta gene or BRCA1 do not have a direct established connection to increased risk for multiple sclerosis. The TGF-beta gene is associated with immune regulation, but its specific involvement in MS susceptibility is less clear. The BRCA1 gene is primarily linked to breast and ovarian cancer risk rather than autoimmune diseases. Furthermore, while the APOE ε4 allele is associated with an increased risk of Alzheimer's disease, it does not contribute to the risk of developing multiple sclerosis. Thus, the HLA-DRB1 allele stands out as the primary genetic factor linked to an increased