Possible association of killer cell immunoglobulin-like receptor genotypes and haplotypes with dry eye disease in a Han Chinese population.

PURPOSE: The objective of this study was to explore whether killer immunoglobulin-like receptor (KIR) genotypes and haplotypes are associated with dry eye disease (DED) in a Han Chinese population. METHODS: Polymerase chain reaction with sequence-specific primers (PCR-SSP) method was used to genotype KIR genes in 106 patients with DED and 220 healthy controls. RESULTS: Twenty-three KIR genotypes were observed in the DED patient and healthy control groups, ten of which had not been described previously. The genotype G and haplotype 4 were associated with increased risk of DED, and the odds ratio (OR) and 95% confidence interval (95% CI) were 2.58, 1.10-6.02 and 2.48, 1.31-4.69, respectively; while haplotype 2 appeared to have an inverse association with the disease (OR, 0.64; 95% CI, 0.44-0.92). Genotype B/B was also associated with increased risk of DED, and the OR and 95% CI were 2.35 and 1.09-5.10, respectively. KIR haplotypes A and B have distinctive centromeric (Cen) and telomeric (Tel) gene-content motifs, and Cen-B/B was associated with increased risk of DED (OR, 2.38; 95% CI, 1.03-5.49). However, all frequencies of these KIR genotypes and haplotypes were no longer statistically significant between the two groups after the Bonferroni correction was applied for multiple testing. CONCLUSIONS: There was a possible association between certain KIR genotypes and haplotypes with DED in a Han Chinese population. However, additional confirmation is required.

Association of killer cell immunoglobulin-like receptor and human leukocyte antigen-C genotype with dry eye disease in a Chinese Han population.

Dry eye is one of the most prevalent eye diseases and dry eye disease (DED) is associated with ocular surface inflammation. The interaction between killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigens (HLAs) regulates the activation of natural killer (NK) cells and certain T cell subsets in response to inflammation. The objective of this study was to explore whether KIR gene and HLA-C allele polymorphisms were associated with DED in a Chinese Han population. Polymerase chain reaction with sequence-specific primers method was used to genotype KIR genes and HLA-C alleles in 106 DED patients and 220 healthy controls. Framework genes KIR2DL4, KIR3DL2, KIR3DL3, and KIR3DP1 were present in all individuals. There were no significant differences in the frequencies of inhibitory KIR genes between the two groups. However, the frequency of KIR2DS2 was significantly higher in severe DED patients than that in healthy controls (p=0.031, odds ratio [OR]=1.828, 95% confidence interval [CI]=1.05-3.17). Significantly different distributions of HLA-C allele groups were not observed in severe DED patients and controls. The frequency of the combination of HLA-C1 allele group with KIR2DS2 was significantly higher in severe DED patients compared with controls (p=0.013, OR=2.083, 95% CI=1.16-3.74). These data suggested that this genotype combination was associated with susceptibility to severe DED and that NK cells might have a role in the pathogenesis of DED. The results led to an interesting future research question of whether or not KIR and HLA-C genotypes were involved in the predisposition to or pathogenesis of DED.