Shrestha Deepika, Rahman Mohammad L, Workalemahu Tsegaselassie, Zhu Chunming, Tekola-Ayele Fasil
Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States.
Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States.
Front Genet. 2018 Nov 2;9:511. doi: 10.3389/fgene.2018.00511. eCollection 2018.
Fetal and maternal genetic propensity to obesity can influence birthweight. We investigated the effects of fetal and maternal genetic risk of obesity on birthweight and evaluated whether these genetic influences modify the well-known association between maternal pre-pregnancy body mass index (BMI) and birthweight. In 950 mother-baby pairs of African ancestry, a genetic risk score for adulthood obesity was generated for mothers (mGRS) and their babies (bGRS) as the weighted sum of BMI-increasing alleles of 97 single nucleotide polymorphisms known to be associated with BMI. The median GRS value was used as a cut-off to define high or low bGRS and mGRS. High bGRS was significantly associated with 70 g lower birthweight (95% Confidence Interval [CI] = -127.4 to -12.4) compared to low bGRS. mGRS was positively correlated with birthweight but the association was not significant. mGRS modified the significant birthweight-increasing effect of maternal pre-pregnancy BMI ( = 0.03); among mothers with low mGRS, those who were overweight or obese had 127.7 g heavier babies (95% CI = 27.1 to 228.2) compared to those who had normal weight. In summary, fetal obesity genetic risk loci exert direct influence on birthweight, and maternal loci modify the effect of pre-pregnancy BMI on birthweight.
胎儿和母亲肥胖的遗传倾向会影响出生体重。我们研究了胎儿和母亲肥胖的遗传风险对出生体重的影响，并评估了这些遗传影响是否会改变母亲孕前体重指数（BMI）与出生体重之间的已知关联。在950对非洲裔母婴中，为母亲（mGRS）及其婴儿（bGRS）生成了成年期肥胖的遗传风险评分，作为97个已知与BMI相关的单核苷酸多态性的BMI增加等位基因的加权和。GRS值的中位数用作界定高bGRS和低bGRS以及高mGRS和低mGRS的分界点。与低bGRS相比，高bGRS与出生体重低70克显著相关（95%置信区间[CI]=-127.4至-12.4）。mGRS与出生体重呈正相关，但这种关联不显著。mGRS改变了母亲孕前BMI对出生体重的显著增加作用（P=0.03）；在mGRS低的母亲中，超重或肥胖的母亲所生婴儿比体重正常的母亲所生婴儿重127.7克（95%CI=27.1至228.2）。总之，胎儿肥胖遗传风险位点对出生体重有直接影响，而母亲的位点则改变了孕前BMI对出生体重的影响。
