Genome-wide association studies (GWAS) have identified DENND1A as a potential candidate gene linked to the fertility-related phenotypes in dairy cows. However, to date, no studies have examined the association of the DENND1A insertion/deletions (indels) to bovine fertility on a large scale. Herein, two indel sites, including P4-del-26-bp and P8-ins-15-bp were identified in 1064 Holstein cows. The values of the minor allelic frequency (MAF) ranged between 0.471 (deletion) and 0.230 (deletion), respectively, and combined four different haplotypes by analyzing the haplotype combination. It is noteworthy that P4-del-26-bp is associated with the ovarian width (P = 0.0004) and corpus luteum diameter (P = 0.004). Meanwhile, P8-ins-15-bp was found to have a significant association with the ovarian width (P = 0.020), ovarian weight (P = 0.004), the number of mature follicles (P = 0.020), and diameter of the mature follicles (P = 0.016). Furthermore, the combinatorial analysis showed that the two indel combined-genotypes were significantly related to several reproductive traits (ovarian width, ovarian weight, etc.). Collectively, our findings indicated that these two novel indels and their combinations are correlated with the reproductive traits, and hence, they can serve in the marker-assisted selection (MAS) in cattle breeding. Nevertheless, further functional experiments are needed for understanding the mechanisms of these indels in cattle reproduction in a better way.

全基因组关联研究 (GWAS) 已将DENND1A确定为与奶牛生育相关表型相关的潜在候选基因。然而，迄今为止，还没有研究大规模检查DENND1A插入/缺失 (indels) 与牛生育能力的关联。在此，在 1064 头荷斯坦奶牛中鉴定了两个 indel 位点，包括 P4-del-26-bp 和 P8-ins-15-bp。次要等位基因频率（MAF）的值分别介于 0.471（缺失）和 0.230（缺失）之间，并通过分析单倍型组合组合了四种不同的单倍型。值得注意的是，P4-del-26-bp 与卵巢宽度（P = 0.0004）和黄体直径（P= 0.004）。同时，发现P8-ins-15-bp与卵巢宽度（P = 0.020）、卵巢重量（P = 0.004）、成熟卵泡数（P = 0.020）和成熟卵泡直径有显着相关性。卵泡 ( P= 0.016）。此外，组合分析表明，两个 indel 组合基因型与几个生殖特征（卵巢宽度、卵巢重量等）显着相关。总的来说，我们的研究结果表明，这两个新的插入缺失及其组合与繁殖性状相关，因此，它们可以用于牛育种中的标记辅助选择 (MAS)。然而，需要进一步的功能实验来更好地理解这些插入缺失在牛繁殖中的机制。