A New DNA Marker of the TMIGD1 Gene Used to Identify High Fertilization Rates in Tsaiya Ducks (Anas Platyrhynchos)

In a prior study, comparisons of individuals of Anas platyrhynchos with higher/lower reproductive performances showed that the expression of the transmembrane and immunoglobulin domain containing 1 (TMIGD1) gene significantly differed between the two groups. Here, we demonstrate that ducks with the TMIGD1 GG genotype have a significantly higher fertilization rate than other TMIGD1 genotypes. Primers designed based on the TMIGD1 sequence of Pekin duck were able to successfully amplify a TMIGD1 fragment from Tsaiya ducks, and sequencing results indicated that a single nucleotide polymorphism (SNP) of the TMIGD1 gene existed. We also developed a cost-effective method of restriction fragment length polymorphism. Using the above methods, ducks were classified into three genotypes. To identify the relationships between genotypes and traits, we recorded the ducks' performance; to ensure the coverage of the entire duration of the fertile period, the egg collection period was extended to 18 days, and therefore, lower than usual fertilization rates were observed. Further assessment using a high-throughput system showed that the ducks with the GG genotype exhibited the highest fertilization rates among genotypes (P < 0.05). We suggest that TMIGD1 may affect the release of sperm protection factors from the female genital tract, and thus alter fertilization rate. In conclusion, the results of this study demonstrate that the TMIGD1 GG genotype can be used as a new DNA marker to identify animals with high fertilization rates at a young age, a process which could improve farming efficiency.