Design and development of a multiplex microsatellite panel for the genetic characterisation and diversity assessment of domestic turkey (<i>Meleagris gallopavo gallopavo</i>)

Domestic turkey production generally utilises only a few genetically improved lines, and local breeds are severely endangered as a result. Furthermore, the genetic resources of domestic turkeys have not been properly investigated, which could, ultimately, lead to the extinction of local breeds and negatively affect their corresponding genetic diversity and environmental adaptation. Although, several microsatellite markers have been designed for mapping and quantitative trait locus analysis, there is no standard panel of markers for genetic characterisation or genetic diversity assessment. Accordingly, the present study aimed to develop a set of polymorphic microsatellite markers that could be used for international turkey population studies. Thirty-nine microsatellites were selected based on polymorphism, DNA sequence and chromosome position, as well as on amplification efficiency, success rate and the absence of nonspecific amplification. The markers were screened using 105 DNA samples from local turkey breeds from Mexico, the United States, Italy, Brazil, Egypt and Spain. A total of 401 alleles were identified, with a mean number of alleles per marker of 10.28 ± 4.25. All microsatellites were polymorphic, with at least four alleles and no more than 19 alleles. Furthermore, allelic richness ranged from 3.810 to 17.985, mean heterozygosity ranged from 0.452 ± 0.229 to 0.667 ± 0.265, polymorphic information content values ranged from 0.213 (MNT264) to 0.850 (RHT0024) and the mean Fis value was 0.322. Overall, the panel was highly polymorphic and exhibited moderate Hardy–Weinberg disequilibrium, thereby indicating its value as a tool for biodiversity and population structure studies that could play an important role in promoting the conservation of local turkey breeds.HighlightsImportant genetic resources reside within indigenous turkey populations. These are linked to historic heritage production values and breeds. It is important to preserve this heritage and genetic diversity, which threatens to be lost as production systems focus on production characteristics.Microsatellite markers, even though, they are now replaced by single nucleotide polymorphism automatic genotyping platforms in many fields of genetics, remain a viable alternative thanks to their cheapness and simplicity of study which makes them particularly useful when the population to be studied lacks information of the prior genetic structure. Important genetic resources reside within indigenous turkey populations. These are linked to historic heritage production values and breeds. It is important to preserve this heritage and genetic diversity, which threatens to be lost as production systems focus on production characteristics. Microsatellite markers, even though, they are now replaced by single nucleotide polymorphism automatic genotyping platforms in many fields of genetics, remain a viable alternative thanks to their cheapness and simplicity of study which makes them particularly useful when the population to be studied lacks information of the prior genetic structure.家火鸡养殖产业通常仅采用少数遗传改良品系，由此导致地方品种陷入严重濒危的困境。此外，家火鸡的遗传资源尚未得到充分探明与研究，这最终可能引发地方品种灭绝，并损害其对应的遗传多样性与环境适应性。此前虽已开发出多种微卫星标记（microsatellite markers）用于遗传图谱构建及数量性状位点分析，但尚未建立用于遗传鉴定或遗传多样性评估的标准化标记组合。 据此，本研究旨在开发一套可用于国际火鸡种群研究的多态性微卫星标记组合。研究基于多态性、DNA序列、染色体位置、扩增效率、成功率及无非特异性扩增等标准，筛选出39个微卫星标记。研究使用来自墨西哥、美国、意大利、巴西、埃及及西班牙的105份本土火鸡品种DNA样本对这些标记进行验证筛选，共鉴定出401个等位基因，每个标记的平均等位基因数为10.28 ± 4.25。所有微卫星标记均呈现多态性，等位基因数介于4至19之间。此外，等位基因丰富度范围为3.810至17.985，平均杂合度范围为0.452 ± 0.229至0.667 ± 0.265，多态信息含量（polymorphic information content）值介于0.213（MNT264）至0.850（RHT0024）之间，平均固定指数Fis值为0.322。总体而言，该标记组合具有高度多态性，且呈现中度哈迪-温伯格不平衡，表明其可作为生物多样性与种群结构研究的有效工具，对推动本土火鸡品种保护具有重要意义。 研究亮点 本土火鸡种群蕴藏着重要的遗传资源，这些资源与历史传承的生产价值及品种特性紧密相关。随着养殖系统聚焦生产性能提升，这类遗传资源与历史传承的遗传多样性正面临丧失风险，因此保护该类资源与遗传多样性至关重要。尽管在众多遗传学研究领域中，单核苷酸多态性（single nucleotide polymorphism）自动基因分型平台已取代微卫星标记，但得益于其低成本与研究简便性，微卫星标记仍是一种可行的替代方案，尤其适用于缺乏预先遗传结构信息的研究种群。 本土火鸡种群蕴藏着重要的遗传资源，这些资源与历史传承的生产价值及品种特性紧密相关。随着养殖系统聚焦生产性能提升，这类遗传资源与历史传承的遗传多样性正面临丧失风险，因此保护该类资源与遗传多样性至关重要。尽管在众多遗传学研究领域中，单核苷酸多态性（single nucleotide polymorphism）自动基因分型平台已取代微卫星标记，但得益于其低成本与研究简便性，微卫星标记仍是一种可行的替代方案，尤其适用于缺乏预先遗传结构信息的研究种群。