Rare damaging recessive genotypes contribute to at least 2.2% of congenital heart disease, with higher prevalence in offspring of consanguineous unions (4.7%) versus nonconsanguineous probands (0.7%).
Observational (n=5,424)
What is the contribution of rare damaging recessive genotypes to congenital heart disease?
Rare damaging recessive genotypes account for at least 2.2% of congenital heart disease cases, with a higher burden in laterality defects and consanguineous families, highlighting the complex genetic architecture of CHD.
Variants with large effect contribute to congenital heart disease (CHD). To date, recessive genotypes (RGs) have commonly been implicated through anecdotal ascertainment of consanguineous families and candidate gene-based analysis; the recessive contribution to the broad range of CHD phenotypes has been limited. We analyzed whole exome sequences of 5,424 CHD probands. Rare damaging RGs were estimated to contribute to at least 2.2% of CHD, with greater enrichment among laterality phenotypes (5.4%) versus other subsets (1.4%). Among 108 curated human recessive CHD genes, there were 66 RGs, with 54 in 11 genes with >1 RG, 12 genes with 1 RG, and 85 genes with zero. RGs were more prevalent among offspring of consanguineous union (4.7%, 32/675) than among nonconsanguineous probands (0.7%, 34/4749). Founder variants in GDF1 and PLD1 accounted for 74% of the contribution of RGs among 410 Ashkenazi Jewish probands. We identified genome-wide significant enrichment of RGs in C1orf127 , encoding a likely secreted protein expressed in embryonic mouse notochord and associated with laterality defects. Single-cell transcriptomes from gastrulation-stage mouse embryos revealed enrichment of RGs in genes highly expressed in the cardiomyocyte lineage, including contractility-related genes MYH6, UNC45B , MYO18B , and MYBPC3 in probands with left-sided CHD, consistent with abnormal contractile function contributing to these malformations. Genes with significant RG burden account for 1.3% of probands, more than half the inferred total. These results reveal the recessive contribution to CHD, and indicate that many genes remain to be discovered, with each likely accounting for a very small fraction of the total.
Dong et al. (Mon,) conducted a observational in Congenital heart disease (n=5,424). Whole exome sequencing was evaluated on Contribution of rare damaging recessive genotypes to CHD. Rare damaging recessive genotypes contribute to at least 2.2% of congenital heart disease, with higher prevalence in offspring of consanguineous unions (4.7%) versus nonconsanguineous probands (0.7%).