The 'Gait keeper' mutation in the DMRT3 gene alters locomotion and gait patterns in horses. This mutation (C>A) has been found in all gaited breeds of horses analyzed but is absent in most non-gaited breeds. We developed a new mutagenically separated polymerase chain reaction (MS-PCR) based method for simple detection of horse DMRT3 genotype. Our method was applied in a preliminary study to determine DMRT3 allele frequencies in 78 Azteca horses (AZ) and 53 Costa Rican Saddle Horses (CRSH). We found a wild-type C allele frequency of 100% in the AZ horses. For the CRSH, the wild-type C frequency and mutant A allele frequency were 88.7% and 11.3%, respectively.

中文翻译：

---

一种新颖的简单基因分型测定法，用于检测DMRT3中的“步态保持者”突变和阿兹台克和哥斯达黎加鞍马品种的等位基因频率。

DMRT3基因中的“步态保持者”突变会改变马的运动和步态模式。在所有被分析的步态马中都发现了这种突变（C> A），但是在大多数非步态马中却没有。我们开发了一种新的诱变分离聚合酶链反应（MS-PCR）为基础的方法，用于简单检测马DMRT3基因型。我们的方法用于初步研究中，以确定78匹Azteca马（AZ）和53哥斯达黎加马鞍（CRSH）的DMRT3等位基因频率。我们在AZ马中发现了100％的野生型C等位基因频率。对于CRSH，野生型C频率和突变A等位基因频率分别为88.7％和11.3％。