The Relationship Between Pulmonary Surfactant Protein C Gene Polymorphism And Preterm Lung Disease In Guangxi

Objective:To study the relationship between single nucleotide polymerph-isms(SNPs) in surfactant protein C (SP-C) gene and neonatal respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD) as well.Methods:207 preterm infants with gestational age<32 weeks were recruit-ed, including 123 preterm infants with RDS (RDS group) and 84 preterm infants without RDS (non-RDS group). Among RDS group,36 preterm infants were diagnosed with BPD (BPD group) and 59 preterm infants without BPD (non-BPD group). Mass Array sequence method was used to genotype 4 tSNPs (rs8192325, rs2070684, rs4715 and rs1124) of SP-C gene and 3 SNPs in promoter (rs8192321, rs8192335, rs8192337). Sanger sequencing method was used to validate the genotyping results in_randomly selected 10 samples of each SNP. the Hardy-Weinberg equilibrium test, haplotype distribution, linkage dise-quilibrium, minor allele frequency (MAF) and genotype frequency of each groups were analyzed by using SHEsis software.Results:① MAF of 4 tSNPs in RDS and non-RDS groups, BPD and non-BPD groups were no significant difference (P>0.05).② 6 haplotypes were found in RDS group and non-RDS group with frequency>0.03. The haplotype GCAA in non-RDS group was significantly higher than that in RDS group (0.000 vs 0.031, P<0.05). There were 6 haplotypes with frequency>0.03 in BPD group and non-BPD group. The frequency of haplotypes GAAA and ACCG in non-BPD group was significantly higher than that in BPD group, with the haplotype ACAA in BPD group higher than that in non-BPD group (0.041 vs 0.000, P<0.05). ③ There was no variants in rs8192321 and rs8192335. Only one heterozygous genotype was found in rs8192337 in RDS group. There were no significant difference between two groups in 3 SNPs (P>0.05). Frequency of 3 promotor SNPs in Guangxi preterm infants were similar with that of Han Chi-nese in Beijing (HCB), but lower than European population from in dbSNP database.Conclusion:①There were no significant association between SP-C gene polymorphism and preterm pulmonary disease. The haplotype GCAA may be a protective factor for RDS, haplotypes of ACCG, GAAA may be protective factors for BPD, and haplotype ACAA may be risk factors for BPD. ② The MAF of 3 SNPs in SP-C promoter in Guangxi preterms cohort is very low and it is unlikely that they provide significant attributable risk for RDS.