法医遗传实验室对X染色体进行越来越多的遗传分析,特别是解决复杂情况下的亲属关系分析。对于某些生物学关系,X染色体标记可以比常染色体标记更多的信息,有大量的标记,已描述用于法医用途的方法和数据库。由于他们特殊的继承方式,以及它们在单个染色体上的物理位置,在估算X染色体标记DNA数据的证据权重时,需要考虑一些具体因素.国际法医遗传学学会(ISFG)的DNA委员会特此提出在亲属关系分析中使用X染色体标记的指南和建议,特别着重于生物统计学评估。连锁和连锁不平衡(等位基因的关联)对于此类评估特别重要,并且更详细地描述了这些概念以及对似然计算的影响。此外,重要的是使用适当的计算机软件来解释基因座之间的连锁和连锁不平衡,以及突变。即使有一些软件存在,仍然需要进一步改进专用软件。
Forensic genetic laboratories perform an increasing amount of genetic analyses of the X chromosome, in particular to solve complex cases of
kinship analysis. For some biological relationships X-chromosomal markers can be more informative than autosomal markers, and there are a large number of markers, methods and databases that have been described for forensic use. Due to their particular mode of inheritance, and their physical location on a single chromosome, some specific considerations are required when estimating the weight of evidence for X-chromosomal marker DNA data. The DNA Commission of the International Society for Forensic Genetics (ISFG) hereby presents
guidelines and recommendations for the use of X-chromosomal markers in
kinship analysis with a special focus on the biostatistical evaluation. Linkage and linkage disequilibrium (association of alleles) are of special importance for such evaluations and these concepts and the implications for likelihood calculations are described in more detail. Furthermore it is important to use appropriate computer software that accounts for linkage and linkage disequilibrium among loci, as well as for mutations. Even though some software exist, there is still a need for further improvement of dedicated software.