%0 Journal Article %T MICA and NKG2D variants as risk factors in spondyloarthritis: a case¨Ccontrol study %J - %D 2018 %R https://doi.org/10.1038/s41435-018-0044-x %X The major histocompatibility complex class I polypeptide-related sequence A (MICA) glycoprotein mediates the activation of the natural killer group 2D receptor (NKG2D) expressed on NK and CD8+ T cells. A methionine or valine at position 129 in exon 3 results in strong (MICA129 met) or weak (MICA129 val) binding to NKG2D. The MICA A5.1 allele causes a premature stop codon. Various NKG2D polymorphisms are associated with low (NKC3 C/C and NKC4 C/C) or high (NKC3 G/G and NKC4 T/T) levels of NK cell cytotoxic activity. In 162 patients with spondyloarthritis (115 with ankylosing spondyloarthritis, 46 with psoriatic arthritis and 1 with reactive arthritis) compared to 124 healthy controls, MICA-129 with methionine allele was more frequent in patients with spondyloarthritis (odds ratio (OR) (95% confidence interval)£¿=£¿4.84 (2.75£¿8.67)), whereas MICA-129 val/val, MICA A5.1 and NKC3 C/C variants were less frequent (OR£¿=£¿0.20 (0.11£¿0.37), 0.15 (0.06£¿0.36) and 0.24 (0.13£¿0.44), respectively). After adjustment for HLA-B*27 status, only NKC3 C/C remained linked to spondyloarthritis (adjusted OR£¿=£¿0.14 (0.06£¿0.33)). Homozygosity for MICA A5.1 is linked to ankylosing spondyloarthritis, and NKC3 C/C and MICA-129 val/val to psoriatic arthritis. MICA and NKC3 polymorphisms (related to a low NK cell cytotoxic activity) constituted a genetic association with spondyloarthritis %U https://www.nature.com/articles/s41435-018-0044-x