Multi-omics analyses reveal new insights into the genetic mechanisms of external genitalia erectile dysfunction in male geese.

Among poultry species, only waterfowl (e.g., goose and duck) possess the external genitalia. Normal erection of the external genitalia in male geese is directly related to mating capability, but its underlying genetic mechanisms remain elusive. In this study, we conducted a multi-omics study on male geese with normal erection (NE) and erectile dysfunction (ED) external genitalia phenotypic, to identify key candidate genes and main molecular networks contributing to external genitalia development differences. Here, we present a comprehensive genome resource for male geese, including a high-coverage (20×) whole genome of 259 samples from Sichuan White Goose × Lande Goose F2 resource population. The genome-wide association study (GWAS) analyses of NE and ED male geese indicated that PCDH7, TFPI, CALCRL, HIBCH, COL3A1, and CAVIN2 may be related to the differences in erectile function of external genitalia. At the transcriptomic level, we identified 318, 629, 2482, and 901 differentially expressed genes (DEGs) in the hypothalamus, pituitary gland, testis, and external genitalia cartilage between NE and ED groups, respectively. Further analysis demonstrated that PCDH7 was identified by both SNP-GWAS and transcriptomic analysis. Integrated with transcriptome data, it was revealed that PCDH7 involved in the function of male goose external genitalia cartilage development may be through MAPK signaling pathway. Collectively, our multi-faceted analysis suggests that PCDH7 affects male geese external genitalia erection may be through the MAPK signaling pathway. Our findings not only provide new insights into the development of external genitalia but also contribute to improving the reproductive performance of male geese.