QF-PCR as a molecular-based method for autosomal aneuploidies detection

Reham Moftah,Christiane Bommer,Dalal El-Kaffash,Mohsen Karbasiyan,Salah Marzouk,Raymonda Varon,Heidemarie Neitzel

doi:10.4236/arsci.2013.13004

Abstract

Objectives: The currently available methods for rapid prenatal diagnosis of common chromosomal aneuploidies are either Interphase-Fluorescence in Situ Hybridisation (I-FISH) or Quanti- tative Fluorescent Polymerase Chain Reaction (QF-PCR). QF-PCR represents a rapid, high throughput, cost-effective alternative for Interphase-FISH. The objective of the study was to evaluate the performance of QF-PCR, as a molecular-based technique for the detection of chromosome 21, 18 and 13 copy numbers. Study design: A retrospective cohort of 163 samples referred for screening of common chromosomal aneuploidies was blindly tested for chromosome 21, 18 and 13 copy numbers using QF-PCR and the results were compared with those of conventional cytogenetic analysis. Results: QF-PCR demonstrated optimal sensitivity and specificity (100%) for non mosaic trisomies. QF-PCR was able to consistently detect maternal cell contamination and mosaic trisomies when the trisomic cell line was present at an adequate level (23% or more). However, QF-PCR was unable to detect chromosomal rearrangements for which the primers were not designed. Conclusion: QF- PCR proved its superior performance as a molecular-based method for autosomal aneuploidy detection concerning both sensitivity and specificity.

Highlights

Autosomal aneuploidies that allow survival to fullterm, namely, trisomy 21, 18, and 13 account for 89% of chromosome abnormalities with a severe phenotype [1,2]
We report our experience concerning the performance of Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) as a molecular technique for the detection of chromosome 21, 18 and 13 copy numbers compared to the gold standard conventional cytogenetic analysis
The results of the QF-PCR were in agreement with those of cytogenetic analyses in 113 out of 120 total abnormalities tested, whereas in the remaining seven samples, the QF-PCR results were either inconclusive or normal (Table 1)

Summary

Introduction

Autosomal aneuploidies that allow survival to fullterm, namely, trisomy 21, 18, and 13 account for 89% of chromosome abnormalities with a severe phenotype [1,2]. Since 1970, the routine using of karyotyping has been regarded as the gold standard for prenatal diagnosis of chromosomal abnormalities. It has the advantage of detecting numerical chromosomal abnormalities, and structural chromosomal rearrangements [3,4]. QF-PCR tests are performed in several prenatal centres in Europe for the detection of major numerical abnormalities affecting chromosomes 21, 18, 13, X and Y, with results provided within a 24 h period [6,7,8,9,10,11,12,13]. Despite the wide range of microsatellite marker multiplexes used by these laboratories, the assays are reported as both robust and reliable [4]

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Conclusion