[Correlation between gene polymorphisms of killer cell immunoglobulin-like receptors and their ligands and Graves'...

Objective: To explore the relationship between gene polymorphism of killer cell immunoglobulin-like receptor (KIR) and its ligand-specific human leukocyte antigen C (HLA-C) and Graves' disease (GD). Methods: Case-control study. A total of 118 unrelated GD patients (GD group) admitted to Shandong Provincial Hospital from January 2011 to December 2017 and 108 age-and sex-matched healthy controls (healthy control group) were included. The KIR genotype and its ligand HLA-C allele were detected by polymerase chain reaction sequence-specific primers (PCR-SSP). The distribution of KIR/HLA-C gene combination in GD patients and control population was analyzed to explore its association with the occurrence of GD. Results: In GD group, there were 29 males and 89 females, aged (38±14) years. In the healthy control group, there were 28 males and 80 females, aged (37±13) years. Compared with the healthy control group, the occurrence frequency of HLA-Cw01 was higher in GD group[36.4%(43/118) vs 18.5%(20/108), P=0.003], and the occurrence frequency of HLA-Cw03 and HLA-Cw06 was lower in GD group[11.9%(14/118) vs 39.8%(43/108), P<0.001; 9.3%(11/118) vs 18.5%(20/108), P=0.045]. The frequency of KIR2DL1/HLA-C2 gene combination in GD group was lower than that in control group [17.8%(21/118) vs 34.3%(37/108), P=0.005]. Logistic regression analysis showed that KIR2DL1/HLA-C2 gene combination was a protective factor for GD occurrence (OR=0.308, 95%CI: 0.126-0.752, P=0.010). Conclusions: The polymorphism of KIR/HLA-C gene is related to GD. The low expression of KIR2DL1/HLA-C2 in GD patients may be a protective factor for GD.