Costa M A P, Bressel R M C, Almeida D B, Oliveira P A, Bassini L N, Moreira C G A, Manzke V H B, Siewerdt F, Moreira H L M
Programa de Pós-Graduação em Zootecnia, Departamento de Zootecnia, Universidade Federal de Pelotas, Pelotas, RS, Brasil.
Genet Mol Res. 2010 Aug 24;9(3):1645-53. doi: 10.4238/vol9-3gmr854.
The goal of this research was to evaluate the ability of the genotyping information available in the Brazilian Criollo Horse Stud Book to describe the genetic variability of the breed and the exclusion probability determined in comparative tests. Altogether, two softwares were used in the analyses of the available genotypes: Cervus 3.0.3 and Genepop 4.0. Eight microsatellite markers totaled 109 alleles, with an average of 13.6 +/- 0.6 alleles per locus. Large differences between expected and observed heterozygosity were ubiquitous (0.821 +/- 0.07 and 0.470 +/- 0.17, respectively). Although the estimated null allele frequency caused initial concern (0.284 +/- 0.199), it is likely that it was a reflection of the inbreeding coefficients found (0.432 +/- 0.184). All loci showed significant deviation from Hardy-Weinberg equilibrium, with heterozygote deficit (P < 0.0001) and genotypic linkage disequilibrium with at least one marker. The high polymorphic information content (0.798 +/- 0.088) could not warrant exclusion power for three loci (HMS7, HMS6 and HTG4) above 50% (0.491 +/- 0.158). However, combined exclusion probability reached 99.61%, a level close to ideal. The results demonstrate the excellent performance of the markers assessed in describing the genetic status of the breed and suggest the considerable ability to establish parentage.
本研究的目的是评估巴西克里奥洛马种马登记簿中可用的基因分型信息描述该品种遗传变异性的能力，以及在比较测试中确定的排除概率。在对可用基因型的分析中总共使用了两个软件：Cervus 3.0.3和Genepop 4.0。八个微卫星标记总共产生了109个等位基因，每个位点平均有13.6±0.6个等位基因。预期杂合度和观察到的杂合度之间存在普遍的巨大差异（分别为0.821±0.07和0.470±0.17）。尽管估计的无效等位基因频率最初引起了关注（0.284±0.199），但它很可能反映了所发现的近亲繁殖系数（0.432±0.184）。所有位点均显示出显著偏离哈迪-温伯格平衡，存在杂合子不足（P < 0.0001）以及与至少一个标记的基因型连锁不平衡。高多态信息含量（0.798±0.088）并不能保证三个位点（HMS7、HMS6和HTG4）的排除能力高于50%（0.491±0.158）。然而，组合排除概率达到了99.61%，接近理想水平。结果表明所评估的标记在描述该品种的遗传状况方面表现出色，并表明其在确定亲子关系方面具有相当的能力。
