Parentage analysis with genetic markers in natural populations. I. The expected proportion of offspring with unambiguous paternity.
Parentage analysis with genetic markers in natural populations. I. The expected proportion of offspring with unambiguous paternity.
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自然群体中遗传标记的亲子分析。
DOI：
10.1093/genetics/118.3.527
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发表时间：
1988
期刊：
影响因子：
3.3
通讯作者：
Smouse,PE
中科院分区：
文献类型：
--
作者：
Chakraborty,R;Meagher,TR;Smouse,PE
最近的研究表明，多态性遗传标记可能有助于解决自然群体中个体之间的谱系关系。当个体之间观察到基因型不相容时，遗传数据提供了亲子关系排除的机会，并且本研究检查了遗传标记在明确的亲子关系确定中的解析能力。假设群体中每个后代的母亲是明确已知的，则对于男性和女性可能来自两个不同基因库的情况，得出被排除在亲子关系之外的男性比例的分析表达式。这一理论公式还可用于预测除一名男性以外的所有男性均可被排除在父子关系之外的每次出生的比例。我们表明，即使平均排除概率接近统一，很大一部分出生也会产生模棱两可的母亲-父亲-后代决定。将明确测定的频率提高到高水平所需的基因座数量超出了大多数物种当前电泳研究的范围。将此理论应用于黄体变色龙 (L.) 的电泳数据表明，在 273 名雄性和 70 名雌性衍生的 2255 个后代中，只有 57 个三联体可以通过 8 个多态性蛋白位点明确确定，即使这些位点的平均组合排除能力为 73%。根据多位点基因型，可以根据这些位点可用的等位基因频率数据合理地预测潜在相容的父本的分布。我们证明，自然群体中的遗传亲子关系分析不能仅基于排除原则可靠。为了衡量自然群体中个体的生殖贡献，必须采用更详细的可能性原则。
Recent studies indicate that polymorphic genetic markers are potentially helpful in resolving genealogical relationships among individuals in a natural population. Genetic data provide opportunities for paternity exclusion when genotypic incompatibilities are observed among individuals, and the present investigation examines the resolving power of genetic markers in unambiguous positive determination of paternity. Under the assumption that the mother for each offspring in a population is unambiguously known, an analytical expression for the fraction of males excluded from paternity is derived for the case where males and females may be derived from two different gene pools. This theoretical formulation can also be used to predict the fraction of births for each of which all but one male can be excluded from paternity. We show that even when the average probability of exclusion approaches unity, a substantial fraction of births yield equivocal mother-father-offspring determinations. The number of loci needed to increase the frequency of unambiguous determinations to a high level is beyond the scope of current electrophoretic studies in most species. Applications of this theory to electrophoretic data on Chamaelirium luteum (L.) shows that in 2255 offspring derived from 273 males and 70 females, only 57 triplets could be unequivocally determined with eight polymorphic protein loci, even though the average combined exclusionary power of these loci was 73%. The distribution of potentially compatible male parents, based on multilocus genotypes, was reasonably well predicted from the allele frequency data available for these loci. We demonstrate that genetic paternity analysis in natural populations cannot be reliably based on exclusionary principles alone. In order to measure the reproductive contributions of individuals in natural populations, more elaborate likelihood principles must be deployed.