多重实时定量PCR快速诊断唐氏及爱德华综合征

目的 建立多重实时定量聚合酶链反应(real-time quantitative polymerase chain reaction,RTqPCR)技术,快速分子诊断唐氏及爱德华综合征.方法 应用PCR方法同时扩增位于21号染色体上的淀粉样前蛋白基因(amyloid precursor protein gene,APP)和18号染色体上的胸苷酸合成酶基因(thymidylate synthetase gene,TYMS),以相对定量指标△CT值区分唐氏、爱德华综合征及正常人.用此方法检测4组样本:36名正常人外周血(A组)、15名正常核型的羊水细胞(B组)、21例唐氏综合征(C组)和6例爱德华综合征(D组).结果 A～D 4组样本△CT均值分别为-0.48±0.15、-0.49±0.12、-1.26±0.17和0.25±0.12.B组与A组间差异无统计学意义(P＞0.05);C组与A组、D组与A组间差异有统计学意义(P＜0.01),且无交叉重叠.结论 多重实时荧光定量PCR技术同时快速诊断唐氏及爱德华综合征是可行的.

Rapid diagnosis of Down's and Edward's syndrome by multiplex real-time quantitative PCR

Objective To establish a multiplex real-time quantitative PCR method for diagnosis of Down's and Edward's syndrome. Methods The sequences of the amyloid precursor protein gene (APP)in the Down's region of chromosome 21 and the thymidylate synthetase gene (TYMS) on chromosome 18 were co-amplified in the same tube. The relative quantitative index △CT value was used to differentiate Down's and Edward's syndrome patient from healthy individual. Four groups of samples, including 36 blood samples from normal controls (group A), 15 amniotic fluid samples from normal pregnancies (group B), 21 samples from patients with Down's syndrome (group C) and 6 samples from patients with Edward's syndrome (group D), were investigated in the study. Results The mean△CT values of the four groups were -0.48±0.15,-0.49±0.12,- 1.26±0.17 and 0.25±0.12 respectively. The △CT value from group B was not different from that from group A (P＞0.05). However, the△CT values from group C and group D were significantly different from that from group A (P＜0.01), and no overlapping was observed.Conclusion The △CT values from multiplex real-time quantitative PCR could be used to rapidly diagnose Down' s and Edward's syndrome simultaneously.