Relationship between arginase genes polymorphisms and preschool wheezing phenotypes.

BACKGROUND

The association between arginase I (ARG1) and arginase II (ARG2) genes and asthma has been reported in previous studies, but associations between polymorphisms in ARG genes and preschool wheezing (PSW) phenotypes are still unknown.

OBJECTIVE

To examine the association between genetic variation in ARG1 and ARG2 genes and PSW phenotypes.

METHODS

We enrolled 83 patients and 86 healthy controls. The patient group included two subgroups: episodic wheezing (EW) (n = 42, median age 41 months) and multiple-trigger wheezing (MW) (n = 41, median age 39 months). We genotyped six single nucleotide polymorphisms (SNPs) in ARG1 and six SNPs in ARG2. Eighteen haplotypes for ARG1 and 31 haplotypes for ARG2 were constituted, and the distributions of SNPs and haplotypes in patients and controls were analyzed.

RESULTS

The frequency of the homozygote cytosine-cytosine (CC) genotype of ARG1 rs2781667T>C SNP and the ARG1 haplotype 4 in the MW group was significantly higher than the EW group (p = .002; odd ratios [OR]: 5.25; confidence interval [CI]: 1.9-14.51 and p < .001; OR: 7.77; CI: 2.54-23.74, respectively). The frequency of the ARG1 haplotype 5 was significantly higher but the frequency of ARG1 haplotype 9 was significantly lower in the all patients than in the healty controls (p = .019; OR: 10.34; CI: 1.28-83.53 and p = .015; OR: 0.093; CI:0.01-0.74, respectively). The frequency of the ARG1 haplotype 2 was significantly higher in the EW group than in the MW group (p = .014; OR: 5.68; CI: 1.48-21.8).

CONCLUSION

Variations in ARG1 may potentially be related to phenotypes and risk of PSW.