Large-scale birth cohorts that recruit trios/duos families are essential resource to enable strategies for determining the environmental and genetic contribution to maternal-infant’s health. However, genomic study based on birth cohorts is still lacking among the Chinese and even the East Asian population. Here, we presented the Phase I genomic study of the Born in Guangzhou Cohort Study (BIGCS) where we conducted whole genome sequencing(~6.63x) and analysis of 4,053 Chinese participants. We detected 56.23 million high-quality genomic variants, 32% are novel in the globe and constructed a reference panel with 4,490 haplotypes that enables more accurate genotype imputation for Chinese population. We characterized the population genetic structure of BIGCS and dissect the genetic relationship of 10 Chinese dialects for the first time. We investigated and compared genomewide associations for multiple complex maternal and infant traits, revealing novel genetic associations with total bile acid, gestational weight gain and lipid metabolism level in maternal peripheral or fetal cord blood. Using an inter-generational mendelian randomization method, we dissected the maternal and fetal genetic effect underlying the associations between maternal phenotypes and fetal growth.
Our findings fill the gap of the missing diversity in human genetics and demonstrate the great value of genomic study of birth cohort in advancing the worldwide maternal-infant health and genetic knowledge.