Gene polymorphism in intron 4 of surfactant protein-B in bronchopulmonary dysplasia infants / 中华围产医学杂志

ABSTRACT

ObjectiveTo investigate the change of gene polymorphorism of surfactant protein-B (SP-B) intron 4 in infants with bronchopulmonary dysplasia (BPD).MethodsForty-five infants with BPD (BPD group) and ninety-nine infants without lung diseases (control group) who admitted into Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology from July 2008 to July 2011 were selected into this study.Genotyping for fragment length polymorphism of SP-B intron 4 was performed by polymerase chain reaction (PCR),agarose gel electrophoresis,cloning and sequencing methods in both groups.Differences of allele frequencies (invariant allele and variant allele) and genotype frequencies (invariant genotype and variant genotype) between BPD group and control group were analyzed.The differences of gestational age and birth weight between the two groups were compared with Independent-Samples t test.The gender composition and differences of allele or genotype frequencies between the two groups were compared with Chi-square test.Results Invariant allele frequencies in BPD group and control group were 83.3％ (75/90) and 92.0％ (182/198),and variant allele frequencies were 16.7％ (15/90,including eight insertion alleles and seven deletion alleles) and 8.1％ (16/198,including eight insertion alleles and eight deletion alleles).There were significant differences between the two groups (x2 =4.75,P =0.029).In BPD group,there were 32 cases (71.1 ％,32/45) invariant genotypes and 13 cases (28.9 ％,13/45,including seven cases insertions and six cases deletions) variant genotypes; in the control group,there were 85 cases invariant genotypes (85.8％,85/99) and 14 cases (14.1％,14/99,six insertions and eight deletions) variant genotypes.Significant difference was found between the two groups (x2=4.42,P＜0.036). ConclusionsVariations of SP-B intron 4 were more in BPD infants,and the variation of SP-B intron 4 might be associated with BPD.