Forensic molecular biological studies of sex chromosomal DNA for the application to criminal and civil identification

1.通过检测Y染色体特异的茧蜂重复序列进行性别鉴定我们建立了用聚合酶链式反应灵敏扩增Y染色体特异的茧蜂重复序列的条件，并从一根长2厘米的毛干上成功地进行了性别鉴定。日本冈山县和广岛县人群中Y染色体微卫星DYS19基因座的等位基因频率估计为A=0.064，B=0.068，C=0.423，D=0.226，E=0.211，F=0.004，C-2=0.004。在这些等位基因中，一个C-2等位基因在凝胶上的B和C等位基因之间迁移，但尚未在所有小种中报道。通过对家庭样本的检验，证实了该STR系统在亲子鉴定中的有效性。此外，这一STR系统有助于识别性侵犯的行凶者。Y染色体上的其他STR基因座DYS390、DYS391和DYS395也被认为在亲子鉴定和性侵犯案件中是有用的。日本冈山县人X染色体Hprt基因座微卫星的等位基因频率估计为T1=0.105，T24=0.243，T3=0.396，T4=0.200，T5=0.057(男84，女63)。该STR基因座可用于亲子鉴定。釉原蛋白基因的检测我们通过限制性内切酶分析和测序，对包括人类雄性和雌性在内的各种动物的扩增产物进行了限制性内切酶分析和测序，结果表明，这些动物之间可能存在区分，除非这些动物在系统发育上是相近的。此外，使用荧光染料标记的引物，可以高灵敏度地检测人类的男性和女性。

1. Sex determination by detection of Y chromosome-specific aiphoid repeat sequenceWe have established the conditions for sensitive amplification of the Y chromosome-specific aiphoid repeat sequence by PCR, and succeeded sex determination from a hair shaft of 2 cm in length.2. Detection of Y chromosomal microsatellite polymorphismsThe allele frequency of a microsatellite DYS 19 locus was estimated to be A=0.064, B=0.068, C=0.423, D=0.226, E=0.211, F=0.004 and C-2=0.004 (N=263) in Japanese living in Okayama and Hiroshima Prefectures. In these alleles, a C-2 allele, migrated between B and C alleles on electrophoretic gels, have not yet been reported in all the races. By the examination of family samples, the usefulness of this STR system in paternity tests was confirmed. Moreover, this STR system was useful for the identification of an assailant/assailants of a sexual assault. The other STR loci on the Y chromosome, DYS 390, DYS391 and DYS395 were also suggested to be useful in paternity tests and in sexual assault cases.3. Detection of an X chromosome microsatellite HPRT polymorphismThe allele frequency of a microsatellite at HPRT locus on the X chromosome was estimated to be T1=0.105, T24=0.243, T3=0.396, T4=0.200 and T5=0.057 (male=84, female=63) in Japanese living in Okayama Prefecture. This STR locus was suggested to be useful in paternity tests.4. Detection of the amelogenin geneWe have examined PCR products from various animals including human male and female amplified using primers for a human amelogenin sequence by restriction enzyme analysis and sequencing, and it was suggested that discrimination between those animals could be possible except that the animals were close phylogenetically. Moreover, using fluorescent dye-labeled primers, human male and female could be determined with high sensitivity by PCR.