[Development and application of real-time quantitative polymerase chain reaction technique using SYBR green I in the diagnosis of Down syndrome]

ABSTRACT

Rapid diagnosis of Trisomy 21 Syndrome [Down Syndrome] patients using Real-Time quantitative Polymerase Chain Reaction [Real-Time qPCR] in order to establish a novel method for prenatal diagnosis in the future. A total of 5 ml of peripheral blood was obtained from each patient and normal controls [NR]. Then, genomic DNA from lymphocytes was extracted using the salting out procedure. Gene dosage levels of DSCAM and [PMP22, DSCAM] in Down Syndrome and NR were analyzed using real-time quantitative PCR. The DSCAM/ PMP22 ratio was calculated according to the 2-delta delta Ct formula for all samples. Real-time PCR showed a DSCAM/PMP22 ratio of 1.48 +/- 0.18 and 1.01 +/- 0.10 [p<0.001] in Down Syndrome and normal samples, respectively, demonstrating three copies of the target [DSCAM] gene in Trisomy 21 Syndrome. DSCAM/PMP22 ratio is increased significantly in Down Syndrome patients than NR [1.5 times]. Therefore, the real-time quantitative PCR technique can be used as a sensitive, accurate and reliable technique for rapid and prenatal diagnosis of Trisomy 21 Syndrome