ABSTRACT
Objective To investigate the association of common polymorphism loci of the cystic fibrosis transmembrane conductance regulator (CFTR) gene with the onset of primary intrahepatic lithiasis (PIL) in the Chinese Han population. Methods A total of 104 patients with PIL who attended The 900th Hospital of PLA Joint Logistics Support Force from June to November 2018 were enrolled as PIL group, and 120 healthy controls who underwent physical examination during the same period of time were enrolled as control group. Sanger sequencing was used to detect the alleles and genotypes at the M470V, TG-repeats, and Poly-T loci of the CFTR gene. The two groups were compared in terms of age, sex ratio, age of onset, and allele and genotype frequencies, and the association of the above three polymorphism loci of the CFTR gene with the risk of PIL was analyzed. The K-S test was used to determine the normality of continuous variables. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the chi-square test was used to compare categorical data and allele/genotype frequencies and analyze Hardy-Weinberg equilibrium. A binary logistic regression analysis was used to investigate the association of genotypes and alleles with the risk of the disease. The association of the loci deviating from Hardy-Weinberg equilibrium with the risk of PIL was expressed as adjusted odds ratio ( OR ). Results There were significant differences between the PIL group and the control group in the distribution of alleles ( χ 2 =15.139, P 0.05). The PIL group had a significantly higher frequency of G allele at the M470V locus than the control group (60.1% vs 41.67%, P < 0.01). Compared with the individuals with AA genotype, the individuals with GG and AG genotypes had a significant increase in the risk of PIL ( OR =4.680 and 2.500, both P < 0.01). As for the TG-repeats locus, the individuals with 12TG/13TG genotype had a significantly higher risk of PIL than those with 11TG/12TG genotype ( OR =11.002, P =0.042), and as for the Poly-T locus, the individuals with 7T/5T genotype had a significantly lower risk of PIL than those with 7T/7T genotype ( OR =0.079, P =0.047). Conclusion The M470V polymorphism of the CFTR gene is independently associated with the risk of PIL in the Chinese Han population, and G allele is a high-risk mutation for the onset of PIL.