Whole genome re-sequencing identifies unique adaption of single nucleotide polymorphism, insertion/deletion and structure variation related to hypoxia in Tibetan chickens

Background: The adaptation to hypoxia in high altitude areas has great research value in the field of biological sciences. Tibetan chicken has unique adaptability to high-altitude, low pressure and anoxic conditions, and served as a biological model to search for genetic diversity of hypoxia adaption.

Methods: The whole genome re-sequencing technology was conducted to investigate the genetic diversity.

Results: In this study, we obtained quantity genetic resource, contained 5164926 single nucleotide polymorphisms (SNPs), 237504 Insertion/Deletion (InDel), 55606 structural variation types in all chromosomes of Tibetan chicken. Moreover, 17154 non-synonymous mutations, 45763 synonymous mutations, 258 InDel mutations and 9468 structural mutations were detected in coding sequencing (CDS) region. Furthermore, SNPs occur in 591 genes, including HIF1A, VEGF, MAPK 8/9/10/11, PPARA/D/G, NOTCH2, and ABCs, which were involved in 14 hypoxia-related pathways, such as VEGF signaling pathway, MAPK signaling pathway, PPAR signaling pathway and Notch signaling pathway. Among them, 19 genes with non-synonymous SNP variation in CDS were identified. Moreover, structure variation in CDS also occurred in the mentioned above genes with SNPs.

Conclusions: This study provides useful targets for clarifying the hypoxia adaptability of the domestication of chickens in Tibetan and may help breeding efforts to develop improved breeds for the highlands.