P53基因多态性及环境因素与低出生体重儿的关系

Relationships among p53 gene polymorphisms,environmental factors and low birth weight infants

【目的】探讨新生儿P53基因多态性及环境因素与低出生体重儿之间是否存在关联。【方法】采用病例对照研究方法,收集母亲和新生儿资料,并根据新生儿出生体重和孕周进行分组,分为健康对照组和低出生体重组,其中低出生体重组包括早产儿组和小于胎龄儿组。使用多聚酶链-限制性片段长度多态性(PCR-RFLP)方法检测其外周血p53基因的2个多态性位点p53codon72、p53PIN3(rs1042522,rs17878362)并比较各自的基因型和等位基因的分布频率。【结果】1)多因素非条件Logistic回归分析显示低出生体重儿的发生与胎儿性别、产妇文化程度、产前检查和居住地有关,回归系数分别为-0.710、1.055、0.825、-0.676。2)p53codon72位点基因型总体分布差异有统计学意(χ2=19.182,P=0.001),而p53PIN3位点的基因型总体分布差异没有统计学意义(χ2=0.566,P=0.754)。p53codon72位点Pro/Pro基因型在早产儿组和小于胎龄儿组的分布明显高于健康对组,其两组携带Pro/Pro基因型风险与健康对照组的OR值分别为2.317(95%CI:1.290～4.162,P=0.002)、2.805(95%CI:1.599～4.919,P=0.000)。【结论】遗传和环境因素及其交互作用在低出生体重儿的发生中均起着重要的作用。p53codon72位点多态性与低出生体重遗传易感性存在相关性,Pro等位基因可能是低出生体重的遗传易感基因。

[Objective] To examine the relationships among p53 gene polymorphisms,environmental factors,and low birth weight infants. [Methods] A case-control study was conducted to collect the data of mothers and newborns,according to birth weight and gestational age,the infants were divided into healthy control group and low birth weight group （including preterm infants group and small for gestational age group）. DNA from peripheral blood samples was examined by potymerase chain-restriction fragment length polymorphism （PCk-RFLP） method to detect the two p53 gene polymorphic situs p53codon72,p53PIN3 （rs1042522,rs17878362） and compared the genotype and allele frequency distribution in three groups. [Results] 1） Multivariate unconditional logistic regression analysis showed that the occurrence of low birth weight infants were associated with fetal gender, maternal education level, prenatal care and place of residence, and the regression coefficients were -0. 710,1. 055,0. 825 ,-0. 676, respectively. 2）There was significant difference in the total distribution frequency of p53codon72 situs（x^2 = 19. 182 ,P= 0. 001）, but no association was detected between the low birth weight group and the healthy control group in p53PIN3 situs （X2 -- 0.566, P = 0.754 ）. The distribution frequencies of Pro/Pro genotype in p53codon72 situs in preterm infants group and small for gestational age group were significantly higher than those in normal birth weight infants group, individuals with the homozygous Pro/Pro genotype had increased risks of low birth weight[（OR：2.317,95%CI：l. 290～4. 162,P：0. 002）, （OR： 2. 805,95%CI.. 1. 599～4. 919,P=0. 000）]. [Conclu- sions] Genetic and environmental factors and their interactions plays an important role in the incidence of low birth weight infants, p53codon72 situs polymorphism is related to low birth weight,and individuals allele of the p53 gene are at increased risk of low birth weight.