The genetic influence on child obesity has not been fully elucidated.
This study investigated the parental and child contributions of 83 adult body mass index (BMI)‐associated single‐nucleotide polymorphisms (SNPs) to obesity‐related traits in children from birth to 5 years old.
A total of 1402 individuals were genotyped for 83 SNPs. An unweighted genetic risk score (GRS) was generated by the sum of BMI‐increasing alleles. Repeated weight and length/height were measured at birth, 1, 2, 3 and 5 years of age, and age‐specific and sex‐specific weight and BMI
Z‐scores were computed. Results
The GRS was significantly associated with birthweight
Z‐score ( P= 0.03). It was also associated with weight/BMI Z‐score gain between birth and 5 years old ( P= 0.02 and 6.77 × 10−3, respectively). In longitudinal analyses, the GRS was associated with weight and BMI Z‐score from birth to 5 years ( P= 5.91 × 10−3 and 5.08 × 10−3, respectively). The maternal effects of rs3736485 in DMXL2on weight and BMI variation from birth to 5 years were significantly greater compared with the paternal effects by Ztest ( P= 1.53 × 10−6 and 3.75 × 10−5, respectively). Conclusions
SNPs contributing to adult BMI exert their effect at birth and in early childhood. Parent‐of‐origin effects may occur in a limited subset of obesity predisposing SNPs.