Department of Health, Medicine and Caring Sciences, Linköping University, 58183, Linköping, Sweden.
Crown Princess Victoria Children's Hospital, and Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden.
BMC Genomics. 2020 Nov 9;21(1):769. doi: 10.1186/s12864-020-07169-7.
Birth weight is determined by the interplay between infant genetics and the intrauterine environment and is associated with several health outcomes in later life. Many studies have reported an association between birth weight and DNA methylation in infants and suggest that altered epigenetics may underlie birthweight-associated health outcomes. However, birth weight is a relatively nonspecific measure of fetal growth and consists of fat mass and fat-free mass which may have different effects on health outcomes which motivates studies of infant body composition and DNA methylation. Here, we combined genome-wide DNA methylation profiling of buccal cells from 47 full-term one-week old infants with accurate measurements of infant fat mass and fat-free mass using air-displacement plethysmography.
No significant association was found between DNA methylation in infant buccal cells and infant body composition. Moreover, no association between infant DNA methylation and parental body composition or indicators of maternal glucose metabolism were found.
Despite accurate measures of body composition, we did not identify any associations between infant body fatness and DNA methylation. These results are consistent with recent studies that generally have identified only weak associations between DNA methylation and birthweight. Although our results should be confirmed by additional larger studies, our findings may suggest that differences in DNA methylation between individuals with low and high body fatness may be established later in childhood.
出生体重是由婴儿遗传和宫内环境相互作用决定的，与以后生活中的多种健康结果相关。许多研究报道了婴儿出生体重与 DNA 甲基化之间的关联，并表明表观遗传学的改变可能是出生体重相关健康结果的基础。然而，出生体重是衡量胎儿生长的一个相对非特异性指标，由脂肪量和去脂体重组成，而这两者可能对健康结果有不同的影响，这促使人们研究婴儿的身体成分和 DNA 甲基化。在这里，我们结合了 47 名足月一周大婴儿的口腔细胞全基因组 DNA 甲基化分析，以及使用空气置换体积描记法对婴儿的脂肪量和去脂体重进行了准确测量。
在婴儿口腔细胞的 DNA 甲基化与婴儿身体成分之间没有发现显著关联。此外，婴儿的 DNA 甲基化与父母的身体成分或母体葡萄糖代谢的指标之间也没有关联。
尽管我们对身体成分进行了准确的测量，但我们没有发现婴儿体脂率和 DNA 甲基化之间的任何关联。这些结果与最近的研究一致，这些研究通常只发现 DNA 甲基化与出生体重之间存在微弱的关联。尽管我们的结果需要通过更多的大型研究来证实，但我们的研究结果可能表明，个体间体脂率的差异可能在儿童后期才会出现 DNA 甲基化的差异。
