利用微卫星标记分析四川8个地方鸡品种遗传多样性

通过选用30个多态性较好的微卫星标记，检测了四川省8个地方鸡品种：峨嵋黑鸡、泸宁鸡、旧院黑鸡、米易鸡、石棉草科鸡、凉山崖鹰鸡、兴文乌骨鸡、沐川乌骨鸡的遗传多样性。利用等位基因频率计算出各群体的平均遗传杂合度（H）、多态信息含量（PIC）和群体间的DA遗传距离。结果表明：30个微卫星位点中有24个微卫星位点在8个鸡群体中的多态信息含量均为高度多态，可作为有效的遗传标记用于各鸡品种的遗传多样性和系统发生关系的分析。各鸡种的杂合度都较高，平均杂合度范围是0.629~0.681，最高的是泸宁鸡（0.681），最低的是旧院黑鸡（0.629）。据分析可能是由于交通闭塞，形成了家禽品种的多种多型，而且杂合度的高低与PIC值的大小体现了较高的一致性。对DA遗传距离的计算表明：用UPGMA法进行聚类分析，结果8个鸡品种被聚为3类：Ⅰ类：峨嵋黑鸡、米易鸡、泸宁鸡、旧院黑鸡聚为一类。米易鸡、泸宁鸡先聚在一起，然后又与峨嵋黑鸡在较近的距离聚在一起，然后再与旧院黑鸡聚在一起；Ⅱ类：石棉草科鸡、兴文乌骨鸡、沐川乌骨鸡聚为一类。兴文乌骨鸡、沐川乌骨鸡在较近的距离聚在一起，然后又与石棉草科鸡在较近的距离聚在一起；Ⅲ类：凉山崖鹰鸡独自聚为一类。这与几个鸡品种的来源、分化、选育历史及地理分布是一致的。

Analysis of Genetic Diversity of Sichuan Indigenous Chicken Breeds Using Microsatellite Markers

Thirty microsatellite markers with medium or high polymorphisms were selected to detect the genetic diversity of 8 indigenous chicken breeds in Sichuan. According to the allele frequencies of 30 microsatellite sites, mean heterozygosity (H), polymorphism information content (PIC) and D_A genetic distances were calculated for each breeds. The results showed that 24 of 30 microsatellite sites were highly polymorphic, so the 24 microsatellite markers were effective markers for analysis of genetic relationship among chicken breeds. The mean heterozygosity of 8 chicken breeds was all over 0.5. The highest was the Luning chicken (0.681), and the lowest was the Jiuyuan Dark chicken (0.629). The high diversity of 8 chicken breeds might be caused by the traffic obstruction(geographic isolation). The results of the heterozygosity were consistent with that of PIC. UPGMA tree was completed through analysis of D_A genetic distances. Emei Dark chicken, Miyi chicken, Luning chicken and Jiuyuan Dark chicken were the first group: Miyi chicken and Luning chicken were grouped firstly, then Emei Dark chicken were grouped with them in shorter time distances, and Jiuyuan Dark chicken were grouped with them at last. Shimiancao Ke chicken Xingwen Silky chicken and Muchuan Silky were the second group: Xingwen Silky chicken and Muchuan Silky were grouped firstly, and then Shimiancao Ke chicken was grouped with them. Liangshangya Ying chicken had its own branch. The result of UPGM was consistent with the genesis, breeding history, differentiation and location of 8 chicken breeds.