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

1. 通过检测Y染色体特异性蚜虫重复序列确定性别我们建立了用PCR灵敏扩增Y染色体特异性蚜虫重复序列的条件，并成功地从一根2厘米长的毛干上确定了性别。Y染色体微卫星多态性检测冈山县和广岛县日本人的微卫星DYS 19位点等位基因频率分别为a =0.064， B=0.068， C=0.423， D=0.226， E=0.211， F=0.004, C-2=0.004 （N=263）。在这些等位基因中，在电泳凝胶上迁移于B和C等位基因之间的C-2等位基因尚未在所有种族中报道。通过家庭样本的检验，证实了该STR系统在亲子鉴定中的有效性。此外，这种STR系统对于识别性侵犯的攻击者或攻击者很有用。Y染色体上的其他STR位点DYS 390、DYS391和DYS395也被认为在亲子鉴定和性侵犯案件中有用。X染色体微卫星型HPRT多态性检测冈山县日本人X染色体HPRT位点微卫星等位基因频率分别为T1=0.105、T24=0.243、T3=0.396、T4=0.200和T5=0.057（男性84例，女性63例）。这个STR基因座被认为在亲子鉴定中是有用的。我们对不同动物（包括人类雄性和雌性）的PCR扩增产物进行了限制性内切酶分析和测序，结果表明，除了在系统发育上接近的动物外，这些动物之间可能存在差异。此外，利用荧光染料标记的引物，可以用PCR方法高灵敏度地确定人的雄性和雌性。

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.