【摘要】 目的获得双方生母均参与情形下计算两个或三个孩子间半同胞关系指数（half-sib index, HSI）的简化公式。方法在给定的前提假设下,根据HSI值的定义,首先推导出单基因座上HSI值的统一表达式,再获得不同基因型组合下的计算公式,最后归纳出两种鉴定情形下的简化公式。将简化公式应用于1例典型的半同胞关系鉴定,根据39个常染色体STR位点的分型计算不同鉴定情形下的累积HSI值。结果成功地推导和归纳出双方生母均参与情形下计算两个或三个孩子间HSI值的简化公式。实际案例的计算结果显示,当双方生母均参与时,任意两个孩子间的累积HSI值与生母均不参与时相比均发生了数量级的改变,即在半同胞关系情形下大约为10⁴～10⁶倍,在无关个体情形下大约为10^-4～10^-3倍。结论所推导出的简化公式可用于计算双方生母均参与情形下两个或三个孩子间的HSI值。更多还原

【Abstract】 Objective To obtain the simplified formulas for calculating the half-sib index（HSI） between two or three children when both mothers are involved in the identification. Methods Under the given premise assumptions, the unified formulas of HSI between two children or three children when both mothers were involved were derived respectively based on the definition of HSI. Then the specific formulas of HSI corresponding to different genotype combinations were also obtained, all of which were subsequently summarized to obtain the final simplified formulas under both circumstances. In addition, according to the genotypes of 39 autosomal STR loci, the formulas were also used in a typical half-sib relationship identification case to calculate the combined HSI（CHSI） values under different situations. Results Simplified formulas were successfully derived and summarized to calculate the HSI between two or three children with both mothers being involved. The calculation results of the real case showed that when both mothers were involved, the CHSI values between any two children change by orders of magnitude compared with the situation where both mothers were not involved, i.e. about 10⁴ ～ 10⁶ times in the half-sib relationship and about 10^-4 ～ 10^-3 times in the unrelated relationship. Conclusion We successfully derived a set of practical and more complete formulas for calculating the HSI values between two or three children when both mothers were involved in the identification.更多还原