GNB3基因C825T多态性及环境因素对儿童体重的影响

目的：探讨GNB3基因C825T多态性及看电视时间对儿童体重的影响。方法：选取大庆地区379名儿童进行5年随访。入选时和第5年分别测定身高、体重，检测GNB3 C825T基因多态性，分为CT型、TT型和CC型．以多因素分析探讨各基因型与儿童体重增长的关系及此基因与看电视时间对儿童体重增加的共同作用。结果：（1）调整年龄、性别因素影响后，初访及5年后，CT/TT基因型组体重（22．87±0．25kg，37．26±0．56kg）均高于CC基因型组（21．89±0．37kg，35．29±0．72kg，均P〈0．05）。多因素线性回归分析显示，调整年龄、性别、出生体重，初访及5年后体重指数均与CT/TT基因型正相关。（2）5年后以每周看电视时间分为3．3h和6．5h2组。看电视时间6．5h组中，CT/TT基因型体重（39．90±0．96kg）显著高于CC基因型（36．39±1．42kg，P〈0．05）。结论：GNB3 C825T基因促进儿童时期体重的增长．并使看电视时间较长的儿童增重更为显著。

Effects of G-protein β3 subunit (GNB3) gene C825T polymorphism and environment :factor on weight change of children in a follow-up study

Objective：To investigate the association of GNB3 gene polymorphism and time of watching-TV with weight change in children.Methods：Three hundred and seventy nine children in elementary schools in Daqing area were enrolled in the present study.Body heights,weights were measured in the 1st and 5th year. The polymorphism of gene was detected by PCR-RFLP and sequencing.Relationship between GNB3 gene C825T polymorphism and children＇s weight,and the common effects of genetic and environmental factors were analyzed by multivariate regression analysis with SAS software package.Results： （1）After adjustment of age and sex,the body weight in group with genotype of CT/TT was all significant higher than that in CC group at the 1st year[（22.87±0.25）kg vs （21.89±0.37）kg,P〈0.05]and 5th year[（37.26±0.56）kg vs（35.29±0.72）kg,P〈 0.05].Multivariate regression analysis showed that the body mass index （BMI）positively correlated with CT/TT genotype after adjustment of age,sex and birth weight at the baseline and 5 years later.（2）When stratified all the subjects to two groups by time of TV-watching （mean time was 3.3 and 6.5h,respectively）at 5 years later,weight of subjects with CT/TT genotype was significant higher than that in subjects with CC genotype [（39.90±0.96）kg vs （36.39±1.42）kg,P〈0.05].Conclusion：GNB3 gene C825T polymorphism significantly correlated with body weight in children,which enhanced weight gain.The increased body weights and BMI in subjects with CT/TT genotype were higher than those with CC genotype by the same time of TV-watehing.