Estudios multicéntricos de la esclerosis múltiple: buscando la heredabilidad perdida

Abstract

Multiple sclerosis (MS) is a neurodegenerative, autoimmune disease of the central nervous system. Genome-wide association studies (GWAS) have identified over hundred polymorphisms with modest individual effects in MS susceptibility and have confirmed that the Major Histocompatibility Complex exerts the greatest individual effect. Additional risk loci with immunologically relevant genes were found significantly overrepresented. Nonetheless, it is accepted that most of the genetic architecture underlying susceptibility to the disease remains to be defined. Candidate association studies of the leukocyte immunoglobulin-like receptor LILRA3 gene in MS have been repeatedly reported with inconsistent results. In an attempt to shed some light on these controversial findings, a combined analysis was performed including the previously published datasets and three newly genotyped cohorts. Both wild-type and deleted LILRA3 alleles were discriminated in a single-tube PCR amplification and the resulting products were visualized by their different electrophoretic mobilities. Overall, this meta-analysis involved 3200 MS patients and 3069 matched healthy controls and did not evidence significant association of the LILRA3 deletion [carriers of LILRA3 deletion: p= 0.25, OR (95% CI)= 1.07 (0.95-1.19)], even after stratification by gender and the HLA-DRB1*15:01 risk allele. In conclusion, we were unable to find any evidence supporting the putative association of the LILRA3 gene with MS risk.