Ablondi Michela, Dadousis Christos, Vasini Matteo, Eriksson Susanne, Mikko Sofia, Sabbioni Alberto
Dipartimento di Scienze Medico-Veterinarie, University of Parma Via del Taglio 10, 43126 Parma, Italy.
Libro Genealogico Cavallo Bardigiano, Associazione Regionale Allevatori dell'Emilia-Romagna, 43126 Parma, Italy.
Animals (Basel). 2020 Jun 8;10(6):1005. doi: 10.3390/ani10061005.
Horses are nowadays mainly used for sport and leisure activities, and several local breeds, traditionally used in agriculture, have been exposed to a dramatic loss in population size and genetic diversity. The loss of genetic diversity negatively impacts individual fitness and reduces the potential long-term survivability of a breed. Recent advances in molecular biology and bioinformatics have allowed researchers to explore biodiversity one step further. This study aimed to evaluate the loss of genetic variability and identify genomic regions under selection pressure in the Bardigiano breed based on GGP Equine70k SNP data. The effective population size based on Linkage Disequilibrium (N) was equal to 39 horses, and it showed a decline over time. The average inbreeding based on runs of homozygosity (ROH) was equal to 0.17 (SD = 0.03). The majority of the ROH were relatively short (91% were ≤ 2Mbp long), highlighting the occurrence of older inbreeding, rather than a more recent occurrence. A total of eight ROH islands, shared among more than 70% of the Bardigiano horses, were found. Four of them mapped to known quantitative trait loci related to morphological traits (e.g., body size and coat color) and disease susceptibility. This study provided the first genome-wide scan of genetic diversity and selection signatures in an Italian native horse breed.
如今，马主要用于体育和休闲活动，一些传统上用于农业的本地品种，其种群数量和遗传多样性急剧减少。遗传多样性的丧失对个体适应性产生负面影响，并降低了一个品种的长期生存潜力。分子生物学和生物信息学的最新进展使研究人员能够进一步探索生物多样性。本研究旨在基于GGP Equine70k SNP数据评估巴尔迪贾诺品种的遗传变异性丧失，并识别处于选择压力下的基因组区域。基于连锁不平衡的有效种群大小（N）等于39匹马，并且随着时间的推移呈下降趋势。基于纯合子片段（ROH）的平均近亲繁殖率等于0.17（标准差 = 0.03）。大多数ROH相对较短（91%的长度≤2Mbp），这突出了较古老的近亲繁殖的发生，而不是近期的近亲繁殖。总共发现了8个ROH岛，在70%以上的巴尔迪贾诺马中共享。其中4个映射到与形态特征（如体型和毛色）以及疾病易感性相关的已知数量性状位点。本研究首次对一个意大利本土马品种进行了全基因组范围的遗传多样性和选择特征扫描。
