【摘要】 【目的】探讨利用21号染色体上STR位点进行唐氏综合征基因诊断的可行性,建立一种快速、准确、简便的唐氏综合征基因诊断方法。【方法】以18例唐氏综合征为研究对象,选择21号染色体上3个STR位点(D21S2052、D21S2054、D21S1446),对外周血DNA进行PCR扩增与聚丙烯酰胺凝胶电泳,根据STR位点出现三条密度定量之比为1∶1∶1带型(完全杂合型)或两条2∶1带型(半杂合型)诊断唐氏综合征,与此同时以细胞遗传学染色体核型分析作为对照。【结果】18例患者在3个STR位点全部出现1∶1∶1带型或2∶1带型,基因诊断结果与染色体核型分析一致。【结论】21号染色体上3个STR位点的基因分型和PCR扩增方法,快速、准确、简便,可用于唐氏综合征基因诊断。更多还原

【Abstract】 【Objective】 To discuss the feasibility of genetic diagnosis of Down’s syndrome using the STR of 21 chromosome and establish a rapid,accurate and fast way diagnosing the Down’s syndrome. 【Methods】 The DNA samples of 18 Down’s syndrome were amplified by PCR and polyacrylamide gel electrophoresis.The diagnosis was made by analyzing allelic distribution at 3 STR locus(D21S2052、D21S2054、D21S1446).In contrary to the karyotype analysis at the same time. 【Results】 All the 18 cases appeared three bands with ratio of 1∶1∶1 or two bands with ratio of 2∶1 in the sites of chosen STRs,which was coincident with the analysis of karyotype. 【Conclusion】 The method of PCR amplification of the three STR locus in the 21 chromosome is rapid,accurate and simple for genetic diagnosis of Down’s syndrome.更多还原