Background: Genetic variants in GARP (also known as LRRC32 ) have been reported to have significant associations with asthma and eczema in special populations, but little is known about allergic rhinitis. This study purposes to evaluate the association of single nucleotide polymorphisms (SNPs) in GARP with house dust mite (HDM)-sensitized persistent allergic rhinitis (PER) in a population of Han Chinese.
Methods: In this hospital-based case–control study, 534 HDM-sensitized PER patients and 451 healthy controls were recruited from East China. In this population, six SNPs in GARP were identified. Serum total and specific IgE levels were measured with ImmunoCAP. Secondary structure and minimum free energy were predicted by RNAfold.
Results: rs79525962 was associated with the risk of HDM-sensitized PER (P < 0.05). The individuals with CT+TT genotype demonstrated a higher risk of HDM-sensitized PER than those with CC genotype (adjusted OR = 1.393, 95% CI = 1.019– 1.904). The homozygous genotype CC of rs3781699 rendered a lower risk of HDM-sensitized PER than the wild-type genotype AA (adjusted OR = 0.646, 95% CI = 0.427– 0.976); however, the genotype and allele frequencies of rs3781699 demonstrated no associations with HDM-sensitized PER (P > 0.05). rs79525962 increased the risk of HDM-sensitized PER in the subgroup aged ≥ 16 years (adjusted OR = 1.745, 95% CI = 1.103– 2.760), and this high risk was also found in the females (adjusted OR = 1.708, 95% CI = 1.021– 2.856). The G-C haplotype of rs1320646-rs3781699 rendered a lower risk of HDM-sensitized PER than the common haplotype G-A (adjusted OR = 0.819, 95% CI = 0.676– 0.993). The secondary structure of GARP altered in response to different genotypes of rs79525962 and rs3781699.
Conclusion: SNP rs79525962 in the GARP gene marks a risk locus of HDM-sensitized PER in Chinese Hans.
Keywords: allergic rhinitis, mites, GARP , LRRC32 , single nucleotide polymorphism, genetic association studies