Study On The Relationship Between SP-C Gene Mutation And Respiratory Distress Syndrome In Neonate Of Mongolian And Han Nationality In Central And Western Inner Mongolia

Objective: Neonatal respiratory distress syndrome(NRDS)has always been a neonatal research hotspot at home and abroad.It is the most common respiratory critical disease in premature infants and has a high incidence rate.In recent years,the correlation between genetic factors and the incidence of NRDS has attracted wide attention.The SP-C gene mutation is a hot research field of new mutation researchs,and the correlation between SP-C gene mutation and the incidence of NRDS has become an important research direction.Therefore,the newborns in the central and western regions of Inner Mongolia are selected as the research object in this project,aiming to study the correlation between the gene variation of SP-C gene exonⅡ,exonⅢ,exonⅣ,exonⅤ and neonatal respiratory distress syndrome in central and western Inner Mongolia,and to provide a new theoretical basis for the prevention and treatment of NRDS.Method: Thirty unrelated NRDS Mongolian and Han NRDS newborns hospitalized in the neonatology department of our hospital were selected as the case group,and 30 unrelated non-NRDS Mongolian and Han newborns in the same time,ethnic group and population were selected as the control group.The newborns in the two groups were matched in gestational age,gender,birth weight and other aspects.Anticoagulant blood samples were retained for all subjects.Genomic DNA was extracted by blood DNA extraction kit.SP-C genes exonⅡ,exonⅢ,exonⅣ and ExonⅤ were amplified by PCR,and the amplified products were sequenced.The gene frequency was calculated by gene counting method,genotype and gene frequency and the significance of difference between groups was compared by Chi-square test,and the correlation between different genotype,allele frequency and the incidence of NRDS was analyzed.Results: 1.In both the case group and the control group,3 cases of SP-C gene exonⅡ region73 gene mutation were detected,the mutation rate was 5.0%.There was no statistical significance in the gene mutation difference between the two groups(P > 0.05),and two genotypes could be detected at this site in both groups: GG and GT,and the frequencies of the two genotypes were the same(95% and 5%,respectively),G allele frequency was 97.5%,and T allele frequency was 2.5%.There was no significant difference in genotype frequency between the two groups(P>0.05),and no significant difference in allele frequency between the two groups(P>0.05).2.There are 3 cases of SP-C gene mutation at 27 locus in exonⅢregion were detected in both the case group and the control group,with a mutation rate of5.0%.There was no statistical significance in the gene mutation difference between the two groups(P >0.05),and two genotypes could be detected at this locus in both groups: The frequencies of the two genotypes were 95% and 5%,respectively.The frequencies of the G allele were 97.5%,and the frequencies of the C allele were 2.5%.There was no significant difference in genotype frequency between the two groups P > 0.05),and no significant difference in allele frequency between the two groups(P >0.05).3.There are 38 cases of SP-C gene mutation at 89 locus in the exonⅣ region of the case group were detected,the mutation rate was 63.3%,and 18 cases of SP-C gene mutation at 89 locus in the exonⅣregion of the control group were detected,the mutation rate was 30.0%,the difference was statistically significant(P<0.05).The frequency of CA genotype in case group was higher than that in control group,while the frequency of CC genotype was lower than that in control group,the difference was statistically significant(P<0.05).The A allele frequency in case group was higher than that in control group,while the C allele frequency was lower than that in control group,and the difference was statistically significant(P<0.05).4.There are 42cases(70.0%)of SP-C gene variation were detected in the case group,and 25 cases(41.7%)of SP-C gene variation were detected in the control group,the difference was statistically significant(P<0.05).GA genotype frequency in case group was higher than that in control group,while GG genotype frequency was lower than that in control group,the difference was statistically significant(P<0.05).The A allele frequency in case group was higher than that in control group,while the G allele frequency was lower than that in control group,and the difference was statistically significant(P<0.05).5.The genotypes and alleles at locus 89 in exonⅣ region were compared between the NRDS newborns of Mongolian and Han in case group,and there was no significant difference in genotype frequency and allele frequency of this locus between the NRDS newborns of Mongolian and Han(P>0.05).The genotypes and alleles at locus 122 in region exonⅤ were compared between the NRDS newborns of Mongolian and Han in case group,and there was no significant difference in genotype frequency and allele frequency of this locus between the NRDS newborns of Mongolian and Han(P>0.05).Conclusions: 1.There is no clear correlation between the gene variation at locus 73 in region exonⅡ and locus 27 in region exonⅢ of SP-C gene and NRDS in neonates in central and western Inner Mongolia.2.Gene variants at locus 89 of SP-C exonⅣ and locus 122 of exonⅤare associated with NRDS in newborns in the central and western regions of Inner Mongolia.Individuals carrying the allele at locus 89 of exonⅣ and locus 122 of exonⅤ of SP-C are at higher risk of NRDS.3.There was no racial difference in genotype frequency and allele frequency of NRDS neonates at locus 89 in exonⅣ and locus 122 in exonⅤ in central and western Inner Mongolia.