[Genetic predisposition to multiple sclerosis as a polygenic autoimmune disease]

Area of Science:

• Immunogenetics
• Neuroimmunology
• Human Genetics

Background:

• Multiple Sclerosis (MS) is a complex autoimmune disease affecting the central nervous system.
• Genetic predisposition plays a significant role in MS etiology.
• Understanding genetic associations in diverse populations like Russians is crucial for unraveling MS pathogenesis.

Purpose of the Study:

• To investigate the association of specific genetic polymorphisms and their combinations with Multiple Sclerosis (MS) in a Russian cohort.
• To identify novel MS-associated genetic factors and confirm previously known ones within this population.
• To explore the genetic heterogeneity of MS based on identified predisposing factors.

Main Methods:

• Case-control study design comparing unrelated MS patients and healthy controls of Russian descent.
• Genotyping of 16 polymorphic loci across DRB1, TNF, LTa, TGFb1, CCR5, and CTLA4 genes, along with TNFa and TNFb microsatellites.
• Utilizing the PSampler algorithm for association analysis of allelic variants and combinations with MS (p<0.01).

Main Results:

• Reidentified previously known MS-associated alleles: DRB1*15(2), TNFa9, and the biallelic combination (CCR5d32, DRB1*04) in the Russian population.
• Discovered novel MS-associated tri-allelic combinations: (-509 TGFb1*C, DRB1*18(3), CTLA4*G) and (-238TNF*B1, -308TNF*A2, CTLA4*G).
• Confirmed the role of autoimmune inflammatory processes in MS pathogenesis through the biological properties of associated genes.

Conclusions:

• The study confirms specific genetic associations with MS in Russians, including known and novel combinations.
• Findings support the concept of MS genetic heterogeneity, with distinct subgroups potentially influenced by different predisposing genetic factors.
• The identified genetic associations reinforce the understanding of autoimmune inflammatory processes as central to MS development.