Analysis of nitric oxide synthase gene polymorphisms in neonatal respiratory distress syndrome among the Chinese Han population

AIM To evaluate the association of NOS1 and NOS3 gene polymorphisms with the risk/severity of neonatal respiratory distress syndrome (RDS) among preterm infants. METHODS The patient group was 189 preterm infants diagnosed with RDS. The control group was 227 preterm neonates who did not develop RDS. NOS genotyping was performed using an improved multiplex ligation detection reaction (iMLDR) technique based on LDR. RESULTS It was found that genotype and allele frequencies of rs2682826 of the NOS1 gene and rs1799983 of the NOS3 gene were not significantly different between the RDS group and the control group. However, when the preterm infants were divided into two and three groups based on gestational age and birth weight, a study of the SNP rs1799983 of the NOS3 gene showed that the GG genotype and G allele frequencies were significantly increased in the RDS groups, the GT genotype and A allele were less frequent among the RDS groups in 26-32.9 weeks of gestational age and in a birth weight subgroup of <1.5 Kg. CONCLUSION Our study raises the possibility that a genetic variation of NOS3 could be implicated in the pathophysiology of RDS in the Chinese Han population, especially in very preterm and very low birth weight infants.