Genome-wide analysis of the role of DNA methylation in inbreeding depression of reproduction in Langshan chicken

摘要

Inbreeding depression of chicken reproduction is a major concern in the conservation of chicken genetic resources. To investigate the potential DNA methylation sites involved in the inbreeding depression of chicken reproduction, we carried out whole-genome bisulfite sequencing (WGBS) of hypothalamus and ovary tissues from the strongly and weakly inbred Langshan chickens, respectively. 5948 and 4593 differentially methylated regions (DMRs) were identified in the hypothalamus and ovary between the strongly and weakly inbred Langshan chickens, respectively. Large numbers of DMR-related genes (DMGs) were enriched in reproductionrelated pathways. By combining the WGBS and transcriptome data, two DMRs in SRD5A1 and CDC27 genes were inferred as the most likely biomarkers of inbreeding depression of reproduction in Langshan chicken. Our study provides the first systematic investigation of the DNA methylation changes in strongly inbred chickens, and extends our understanding of the regulatory mechanisms underlying inbreeding depression in chicken reproduction.