Relationship Of Endothelial Nitric Synthase Polymorphism And The Nural Tube Defects

Objective:To understand the birth prevalence and the epidemiological status of Neural Tube Defects in Shi-hezi city of Xinjiang province, and study the relationship between the gene polymorphism of endothelial nitric synthase and the Neural tube defects, invest the danger factors about it,so as to provide theory evidence to prevent it.Methods:The newborns aged from 28 weeks of gestation to 7 days of age in 23 hospitals of Shi-hezi city over a period from Jan.2001 to Dec.2008 were monitored for Neural Tube Defects.And the mid-gestation cases from Jan.2008 to Sep.2009 were diagnosed through B type ultrasonic in the first hospital affiliated to Shi-hezi university, theirs blood sample were collected. It was designed as 1:2 matched case-control study.We choose 30 patients who had given birth to NTDs children as case group and 60 patients given birth to normal children as control group from our hospital. All of the objects were given same questions about suspected risk factors for NTDs,and their polymorphism of G894T and 4a/b VNTR of eNOS gene were analyzed by a combination of polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP).All of the data was analysized with SPSS16.0 statistical software.Result:①A total of 24417 births wer registered in 8 years.The average birth prevalence of NTDs was 16.38 per 10000 births,the prevalence in countryside and city proper were 26.26 per 10000 and 6.54 per 10000,respectively.②The result of analysis of logistic regression show that morther eNOSG894T mutation,but not eNOS 4a/bVNTR was one of the genetic risk factors of offspring NTDs. Eating folate acid during periconceptional was environmental protective factor,while pesticide and fertilizer were environmental risk faetor for NTDs.③There have significant differences of genotypes and the allele frequencies of eNOSG894T between control and cases, the frequencies of GG,GT and TT genotypes were 46.67%,40%,13.33% respectively in case group, and 73.33%,21.67%,5% for control group(χ2=43.57, p<0.001). Allele frequeneies of G and T were 66.7% and 33.3% in case group respectively, and 84.2% and 15.8% in control group(x2=7.218, p<0.01).④While as for eNOS 4a/b VNTR,the genotypes and the allele frequencies have no distinctly difference between case and control groups,the frequencies of bb and aa genotypes were 63.33% and 36.67% respectively in case group, and 80% and 20% in control group(p>0.05). Allele frequeneies of b and a were 81.7% and 18.3% in case group respectively, and 90% and 10% in control group(p>0.05).⑤Analysis of interaction between factors showed that:pesticide and fertilizer may increace the neural tube defects risk in the mothers who has gene mutation of eNOSG894T.Conclution:It was suggested that not mother eNOS4a/b VNTR, but G894T mution was one of the independent genetic risk factors of offsprings NTDs. Eating folate acid during periconceptional was environmental protective factor,while medication, pesticide and fertilizer were environmental risk faetor for NTDs.As for the mother has eNOSG894T mutation, pesticide and fertilizer can increase the risk of NTDs.