Distribution of surfactant protein A2 haplotype and its association with preterm respiratory distress syndrome susceptibility

Abstract

Objective To study the distribution of surfactant protein A2(SP-A2) haplotype and its association with preterm respiratory distress syndrome (RDS) susceptibility in a local Chinese cohort. Methods Using population base and case-control study cohorts, genotyping for four single nucleotide polymorphism (SNP) was performed, rs1059046, rs17886395, rs1965707, rs1965708, in 80 term infants, 50 preterm infants with RDS(RDS group) and 50 preterm infants without RDS(control group) by using TaqMan®real-time polymerase chain reaction.Infants in RDS group and control group were matched according to gender and gestational age.Frequency of each haplotype was compared between preterm infants with RDS and without RDS, term infants and preterm infants without RDS. Results Most common haplotypes in term infants were 1A0, 1A5, 1A1.In each preterm infants groups with RDS and without RDS, 1A0, 1A5, 1A1 were also the most common haplotypes.Among these three common haplotypes, frequency of 1A0 was lower in preterm infants, including RDS group and control group, than that in term infants.No significant difference was found between preterm groups with RDS and without RDS(P>0.05), neither in preterm infants with gestational age ≥32 or <32 weeks.Haplotype 1A0 frequency(0.542) in term infants was significantly higher than that in preterm infants<32 weeks without RDS(0.329)(χ2= 6.06, P=0.01). Conclusions SP-A2 haplotype distribution in a local Chinese population shows ethnic characteristics to some extent.Only SP-A2 does not contribute to the susceptibility for preterm RDS. Key words: Surfactant protein A2; Haplotype; Respiratory distress syndrome; Infant, preterm