Expression pattern of heme oxygenase 1 gene and hypoxic adaptation in chicken embryos

Heme oxygenase 1 (HO-1), a rate-limiting enzyme of heme catabolism, has a crucial role of cytoprotective functions under hypoxia. The objective of the present study was to investigate potential differences in protective effect of HO-1 gene on chicken (Gallus gallus) embryo lung during late incubation. At embryonic day (D) D16, D18, D19, and D20 of incubation, the expression of HO-1 in the lungs of chicken embryos (Tibet and Shouguang chickens) incubated in normoxic (21% O2) and hypoxic (13% O2) conditions was measured. SNPs were screened within 5′-flanking region and coding regions with PCR-sequencing and the genotype of the SNPs was determined with PCR-RFLP in Tibet, Chahua and Shouguang chicken populations. In conclusion, the Tibet chicken had higher HO-1 expression on D19 under hypoxic incubation and had two SNPs with different frequency distributions from other chicken breeds, which might be a way that the Tibet chicken had hereditary adaptation to hypoxia during embryonic development.