ELOVL2基因多态性与乳母乳汁DHA水平的关联性分析

Association analysis on polymorphisms of ELOVL2 gene and DHA level in breast milk of lactating mothers

目的：探讨 ELOVL 脂肪酸延长酶基因2（ELOVL2）rs2281591和 rs3798713位点与乳母乳汁二十二碳六烯酸（DHA）水平的关系，阐明 ELOVL2基因多态性对乳汁 DHA 水平的影响。方法：选取健康产妇209人，在产后第22～25天签署知情同意书并进行三天二十四小时膳食回顾调查，收取乳汁20 mL，应用气相色谱法检测乳汁 DHA 水平，并提取乳汁基因组 DNA，应用 Sequenom Mass Array 系统检测 ELOVL2基因2个单核苷酸多态性（SNP）位点基因型，采用 UNPHASED 3.012遗传学软件进行多位点单倍型与乳汁 DHA 水平的数量性状分析。结果：ELOVL2基因 rs2281591和 rs3798713位点基因型频数分布均符合 Hardy-Weinberg 平衡定律（P ＞0.05）；不同基因型的乳母膳食脂肪酸摄入量和乳汁 DHA 水平差异均无统计学意义（P ＞0.05）；不同 rs3798713（CG）-rs2281591（AG）单倍型的乳母乳汁 DHA 水平比较差异无统计学意义（χ2＝3.422，df ＝5，P ＝0.635）。结论：ELOVL2基因 rs3798713和 rs2281591位点及其组成的单倍型与乳母乳汁 DHA 水平无关联。

Objective To investigate the association between rs2281951 and rs3798753 in ELOVL fatty acid elongase2 （ELOVL2 gene）and the docosahexenoic acid （DHA）level in breast milk,and to clarify the influence of the polymorphisms of ELOVL2 gene in the DHA level of breast milk.Methods 209 healthy maternals were selected and signed the consent form and completed the 3-day 24-hour dietary recall questionaire on one day during the 22nd-the 25th day after partum,and 20 mL breast milk was collected.The DHA level in breast milk was detected with gas chromatography.The milk DNA was extracted and two single nucleotide polymorphisms （SNPs） of ELOVL2 gene were detected by Sequenom Mass Array System. UNPHASED 3.012 genetics software was adopted to analyze the quantitative trait of haplotype and the DHA level in breast milk.Results The distribution of genotypic frequencies of rs2281591 and rs3798713 sites in ELOVL2 gene was consistent with Hardy-Weinberg equilibrium （P 〉 0.05）.The dietary fatty acid intakes and the milk DHA levels of maternals carrying different genotypes had no statistically significant differences （P 〉 0.05 ）. The DHA levels in breast milk of maternals carring different rs3798713 （CG）-rs2281591 （AG）haplotypes had no statistically significant difference （χ2 =3.422,df =5,P =0.635）.Conclusion Rs3798713 and rs2281951 and constructed haplotypes in ELOVL2 gene are not related to the DHA levels in breast milk.