A Study On The Correlation Between SP-B Intron 5 Polymorphism And Bronchopulmonary Dysplasia In Mongolian And Han Populations

Objective Bronchopulmonary dysplasia(BPD)is commonly seen in preterm infants.The smaller the gestational age is,the higher the risk is.In recent years,with the rapid development of medical technology,the rescue rate of premature infants has gradually increased,and the incidence of BPD has also increased.BPD is caused by a combination of high-risk factors,and its nature is genetic susceptibility,and the damage caused by oxygen poisoning,barotrauma or volume injury,and infection or inflammation to immature lung tissue,as well as abnormal repair of lung tissue damage.The main role of pulmonary surfactant protein B(surfactant protein,SP-B)is to maintain the stability of the alveolar structure,and at the same time can inhibit exotoxin-induced inflammation of the lung.It plays an important role in maintaining normal lung function and pulmonary inflammatory response.The pathogenesis of lung disease.In recent years,some studies have shown that SP-B intron 5may be involved in the occurrence and development of BPD.In this study,a case-control analysis of the association between SP-B intron 5 gene polymorphisms and BPD was performed.Methods Mongolian and Han babies with BPD who were hospitalized in the Department of Neonatology at the Affiliated Hospital of Inner Mongolia Medical University from October 2014 to October 2017 were included as the case group.The control group consisted of babies with non-BPD at the same time in Mongolian and Han ethnic groups.The ratio of case group to control group was 1:1.The polymerase chain reaction(PCR)gene analysis technique was used to examine the genotype and allelic distribution of SP-B intron 5.Results A total of 100 premature infants of Mongolian and Han nationality were included,including 50 BPD and 50 non-BPD groups.Three genotypes were detected in the SP-B intron5 genes of the Mongolian and Han case groups: invariant type,insertion type,and deletion type.Among them,the frequency of invariant type,insertion type and deletion type ofMongolian BPD group were 56%,16%,and 28%,respectively,and the allele frequencies were 60%,22%,and 18%.The frequencies of genotypes of invariant type,insertion type and deletion type were 64%,22%,and 14% in the control group,respectively,and the allele frequencies were 68%,16%,and 16%,respectively.In the Han nationality,the frequencies of the invariant-type,insertion-type and deletion-type genotypes in the BPD group were 62%,22%,and 16%,respectively,and the allele frequencies were 68%,18%,and 14%,respectively.The frequencies in the control group of genotypes were 56%,24%,and 20%,and the allele frequencies were 62%,22%,and 16%,respectively.The frequency of SP-B intron 5 alleles and genotype frequencies in children with either Han or Mongolian BPD was not statistically significant compared with the control group(P>0.05).Conclusion The polymorphism of SP-B intron 5 is not significantly associated with the occurrence and development of BPD in preterm infants of Mongolian and Han nationality.The distribution of genotype and allele frequencies is not significantly different between Mongolian and Han populations.