足月新生儿呼吸窘迫综合征SP-B+1580基因突变分析

Analysis of gene mutation in surfactant protein B+1580 site on full-term newborns with respiratory distress syndrome

【目的】分析SP-B+1580基因突变与足月新生儿呼吸窘迫综合征(respiratory distress syndrome,RDS)的相关因素。【方法】312例汉族足月RDS新生儿作为RDS组和156例汉族足月健康新生儿作为对照组。PCR扩增SP-B exon4并测序;免疫组化技术分析肺部SP-B和proSP-B表达。【结果】两组SP-B+1580位点存在CC、C/T、TT3种基因型,RDS组C/T基因型频率明显高于对照组(P<0.05)。具有C/T基因型的RDS患儿,剖宫产、机械通气、死亡的发生率较其他基因型高,胸片显示RDS程度较重、需要肺表面活性物质的剂量大[200mg/(kg.次),3～4剂](P<0.01)。50例伴有C/T基因型的RDS死亡患儿中有19例患儿成熟SP-B和proSP-B蛋白肺部表达减少。【结论】SP-B+1580位点C/T基因型可引起成熟SP-B和proSP-B蛋白在肺部的减少,是足月新生儿RDS发病的高危因素。

【Objective】 To analyze correlative factor between gene mutation（SP-B ＋1580） and respiratory distress syndrome（RDS） in full-term newborns.【Methods】 There were 312 Han full-term newborns with RDS as RDS group and 156 Han healthy full-term newborns as control group.Genotypic analysis on exon 4 was performed with polymerase chain reaction amplification（PCR） and gene sequencing.Analysis of for expression of SP-B and proSP-B in lung were determined with immunohistochemical technique.【Results】 Three genotypes of SP-B＋1580 including CC,C/T,TT were discovered in two groups.Frequency of C/T genotype in RDS group was higher than that in control group（P0.05）.Patients with C/T genotype had higher rates on uterine-incision delivery mechanical ventilation and mortality chest X-ray grade showed severity about RDS,and needed more pulmonary surfactants（P0.01）.19 patients with decreased mature SP-B and proSP-B were among 50 cases of dead patients with C/T genotypes.【Conclusion】 C/T genotype in SP-B ＋1580 site causing decreased mature SP-B and proSP-B may be the high risk for RDS.