Edwards A, Civitello A, Hammond H A, Caskey C T
Institute for Molecular Genetics, Baylor College of Medicine, Houston, TX 77030.
Am J Hum Genet. 1991 Oct;49(4):746-56.
Tandemly reiterated sequences represent a rich source of highly polymorphic markers for genetic linkage, mapping, and personal identification. Human trimeric and tetrameric short tandem repeats (STRs) were studied for informativeness, frequency, distribution, and suitability for DNA typing and genetic mapping. The STRs were highly polymorphic and inherited stably. A STR-based multiplex PCR for personal identification is described. It features fluorescent detection of amplified products on sequencing gels, specific allele identification, simultaneous detection of independent loci, and internal size standards. Variation in allele frequencies were explored for four U.S. populations. The three STR loci (chromosomes 4, 11, and X) used in the fluorescent multiplex PCR have a combined average individualization potential of 1/500 individuals. STR loci appear common, being found every 300-500 kb on the X chromosome. The combined frequency of polymorphic trimeric and tetrameric STRs could be as high as 1 locus/20 kb. The markers should be useful for genetic mapping, as they are sequence based, and can be multiplexed with the PCR. A method enabling rapid localization of STRs and determination of their flanking DNA sequences was developed, thus simplifying the identification of polymorphic STR loci. The ease by which STRs may be identified, as well as their genetic and physical mapping utility, give them the properties of useful sequence tagged sites (STSs) for the human genome initiative.
串联重复序列是用于遗传连锁分析、图谱绘制和个人识别的高度多态性标记的丰富来源。对人类三聚体和四聚体短串联重复序列（STR）进行了信息性、频率、分布以及DNA分型和遗传图谱绘制适用性的研究。这些STR具有高度多态性且遗传稳定。描述了一种基于STR的用于个人识别的多重PCR。其特点包括在测序胶上对扩增产物进行荧光检测、特定等位基因识别、独立位点的同时检测以及内部大小标准。探讨了四个美国人群中等位基因频率的变化。荧光多重PCR中使用的三个STR位点（4号、11号染色体和X染色体）的综合平均个体识别潜力为1/500个体。STR位点似乎很常见，在X染色体上每300 - 500 kb就有一个。多态性三聚体和四聚体STR的组合频率可能高达1个位点/20 kb。这些标记对于遗传图谱绘制应该是有用的，因为它们基于序列，并且可以与PCR进行多重反应。开发了一种能够快速定位STR并确定其侧翼DNA序列的方法，从而简化了多态性STR位点的识别。STR易于识别，以及它们在遗传和物理图谱绘制方面的实用性，使其具有作为人类基因组计划中有用的序列标签位点（STS）的特性。
