Association of single nucleotide polymorphisms in the vitamin D receptor gene with the clinical outcome of influenza in children / 中国小儿急救医学

ABSTRACT

Objective:To investigate the association of single nucleotide polymorphisms(SNPs)in the vitamin D receptor(VDR)gene with influenza susceptibility and severity of disease in children.Methods:Peripheral venous blood was collected from 172 children with influenza A (study group) and 88 healthy children (healthy control group) admitted to Xi ′an Children′s Hospital and Xi ′an Central Hospital from February 2019 to February 2021.Serum 25-hydroxyvitamin D(25-OH-D) level was detected by using 25-OH-D kit.The study group was divided into three groups according to clinical syndrome mild group, severe group, and critical group.Four candidate loci in the VDR gene(ApaI, TaqI, FokI, and BSMI)were selected, and polymorphisms in the VDR gene of each group were determined by polymerase chain reaction restriction fragment length polymorphism and analyzed in relation to children with influenza.Results:Compared with the healthy control group[(109.65±4.35) nmol/L], the serum 25-OH-D levels in the study groups were lower[(73.55±2.46)nmol/L in the mild group, (45.59±4.62) nmol/L in the severe group, and (33.65±3.87) nmol/L in the critical group]( P<0.05); Genotypes AA, Aa and allele A of the ApaI locus(51.74%, 22.67%, and 63.08%, respectively)and genotypes FF, Ff and allele F of the FokI locus(41.86%, 34.88%, and 59.30%, respectively)accounted for a significantly higher proportion of cases in the study group than those in healthy control group(11.36%, 14.77%, 18.75%, 10.23%, 13.64%, and 17.05%, respectively)( P<0.05). The proportion of allele A at the ApaI locus and genotypes AA and Aa in severe group(63.70%, 43.84%, and 28.76%) were significantly higher than those in mild group(47.37%, 35.09%, and 24.56%)( P<0.05); The proportion of allele A and genotype AA and at the ApaI locus in critical group(92.86%, 88.10%, and 49.52%) were significantly higher than those in severe group( P<0.05). Serum 25-OH-D<50 nmol/L( OR=5.087, 95% CI 3.114-5.648), ApaI site genotypes AA ( OR=4.011, 95% CI 1.217-18.624)and Aa( OR=3.839, 95% CI 2.483-1.456), FokI site genotypes FF( OR=4.112, 95% CI 3.215-20.775)and Ff( OR=4.591, 95% CI 0.032-10.936)were risk factors for the onset of influenza in children. Conclusion:Serum 25-OH-D deficiency is associated with childhood influenza, and VDR gene genotype AA and Aa of ApaI locus, and FokI site genotype FF, Ff may increase the risk of childhood influenza susceptibility, and allele A of ApaI locus and genotypes AA and Aa are associated with the severity of influenza.