Insertion/deletions within the bovine FoxO1 gene and their association analysis with growth traits in three Chinese cattle breeds.

() gene, as a transcription factor, plays a vital role in animal growth and development, participating in many biological processes. The aim of this study was to ascertain Insertion/deletions (Indels) polymorphism within bovine gene in 679 Chinese adult cows and associate them with stature traits. Two Indels (named as Indel-3 and Indel-4, recorded as rs383545622 and rs525318770 in NCBI, respectively) were successfully genotyped by the Once PCR method, which was reliable, rapid and cost effective for simultaneous detection of two or more Indels. Indel-3 and Indel-4 were located at the second intron. All four different haplotypes (H1: DD, H2: ID, H3: DI, H4: II) could be identified, and the D (del-) allele, DD (del-/del-) genotype and DD haplotype retained the highest frequency. However, individuals with DI (DI, DI or H1H4/H2H3 genotype) showed significantly better phenotypic traits than those with the other genotypes in Nanyang cattle, showing a hybrid vigor. The results implied that this DI genotype can be applied to early selective breeding to improve the productivity of Nanyang cattle. Our results suggested that these two Indels within the bovine gene might be used as genetic markers for marker-assisted selection (MAS) in cattle breeding and genetics.