Fang Jian-Xin, Zhao Shu-Min, Li Cheng-Tao, Zhang Su-Hua, Li Li
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, Shanghai, China.
Fa Yi Xue Za Zhi. 2009 Oct;25(5):341-4.
To establish and evaluate the method of matched locus numbers in full sibling identification.
Two hundred and eighty full sibling (FS) pairs and 2003 unrelated individual (UI) pairs were genotyped with Identifiler system. The number of locus matched with 0 identical allele (A0), matched with 1 allele (A1) or matched with 2 alleles (A2) were counted and full sibling index (FSI) were calculated based on ITO method. Fisher discriminant functions were established based on the numbers of matched STR locus or FSI. Power of different Fisher discriminant functions was statistically analyzed.
The distribution of A1 and A2 in FS group and that of A0 and A1 in UI group were in accord with normal distribution. Contrarily, A0 in FS group and A2 in UI group fitted to skew distribution, respectively. Difference of A1 distribution was not statistically significant in the two groups (P>0.01). The established Fisher discriminant functions based on A0 and A2 for each group were Z(FS)=0.99817A0+4.24442A2-12.77970 and Z(UI)=2.01456A0+1.54658A2-7.28076, respectively, the average error probability of which was as low as 0.0490. The power of discrimination for full sibling showed no statistically significant difference between ITO method and the established Fisher discriminant functions.
The number of matched STR locus in Identifiler system is a valuable method in full sibling identification. The discriminating power of the established Fisher discriminant functions based on the matched STR locus number is similar with that of classic ITO method in full sibling identification.
建立并评估全同胞鉴定中匹配基因座数目的方法。
采用Identifiler系统对280对全同胞（FS）和2003对无关个体（UI）进行基因分型。统计0个相同等位基因匹配（A0）、1个等位基因匹配（A1）或2个等位基因匹配（A2）的基因座数目，并基于ITO方法计算全同胞指数（FSI）。基于匹配的STR基因座数目或FSI建立Fisher判别函数。对不同Fisher判别函数的效能进行统计学分析。
FS组中A1和A2的分布以及UI组中A0和A1的分布符合正态分布。相反，FS组中的A0和UI组中的A2分别拟合偏态分布。两组中A1分布的差异无统计学意义（P>0.01）。为每组建立的基于A0和A2的Fisher判别函数分别为Z(FS)=0.99817A0 + 4.24442A2 - 12.77970和Z(UI)=2.01456A0 + 1.54658A2 - 7.28076，其平均错误概率低至0.0490。全同胞的判别效能在ITO方法和建立的Fisher判别函数之间无统计学显著差异。
Identifiler系统中匹配的STR基因座数目是全同胞鉴定中的一种有价值的方法。基于匹配的STR基因座数目建立的Fisher判别函数在全同胞鉴定中的判别能力与经典ITO方法相似。
