A novel competitive fluorescent multiplex STR polymorphism assay for rapid, reliable and single-tube screening of 22q11.2 copy-number aberrations
ABSTRACT Copy-number aberrations of the 22q11.2 region can lead to varied resulting and complex phenotypes. Routine screening for these common constitutional chromosomal abnormalities requires powerful tools. A competitive fluorescent multiplex STR polymorphism assay (CFMSA) was built for detecting these aberrations. With the introduction of an internal reference and distinguishable STR polymorphism markers, this competitive fluorescent multiplex STR polymorphism assay provides complementary information about polymorphism and gene dosage in one tube simultaneously, thereby enhancing the assay sensitivity. It was first tested in 110 normal controls, and was proven to have highly polymorphic and reliable gene dosage information. Then, 476 subjects with congenital heart defect were screened according to the testing strategy of the American Heart Association, and 17 deletions and 1 duplication of 22q11.2 were correctly identified. It is expected that this assay will serve as a cost-effective alternative to existing assays for routine, large-scale screening in all at-risk individuals with either deletion or duplication in 22q11.2.
Conference Paper: Exact BER computation for the cross 32-QAM constellation[Show abstract] [Hide abstract]
ABSTRACT: When the number of bits per symbol is odd, the peak and average power of transmission can be reduced by using cross quadrature amplitude modulations (QAMs) instead of rectangular QAMs. Since perfect Gray coding is not possible for cross QAMs, using Smith-style Gray coding, we derive in this paper the exact bit error rate (BER) for the cross 32-QAM constellation over additive white Gaussian noise (AWGN) and Rayleigh fading channels.Control, Communications and Signal Processing, 2004. First International Symposium on; 02/2004
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ABSTRACT: Small submicroscopic DNA copy number variants represent an important source of variation in the human genome, human phenotypic diversity, and disease susceptibility. Consequently, there is a pressing need for the development of methods allowing the efficient, accurate, and cheap measurement of genomic copy number polymorphisms in clinical cohorts. The PCR-based strategies, being cost-effective and sensitive, are considered important in the development of screening techniques. PCR-based techniques such as multiplex PCR; multiplex ligation-dependent probe amplification; and a new single-tube assay technique, the competitive fluorescent multiplex STRP assay, have been applied to 22q11.2 detection, a typical example of deletion syndromes. In this study, we compared the reliability and application of these three techniques in a cohort of 17 patients affected with 22q11.2 deletion and 300 normal controls. All three techniques shared 100% sensitivity; however, the competitive fluorescent multiplex STRP assay had the lowest possibility of concurrent false-positive signals from two adjoining probes in a genomic region. Moreover, it is a relatively fast and low-cost procedure to detect the deletion of 22q11.2 in numerous patients with several minor symptoms of deletion syndromes. Multiplex PCR, a rapidly developing and cheap technique, allows detection of atypical deletions.Genetic Testing and Molecular Biomarkers 12/2009; 13(6):803-8. DOI:10.1089/gtmb.2009.0058 · 1.15 Impact Factor
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ABSTRACT: People carrying a 22q11.2 microduplication display a phenotype varying from normal to severely affected. We report a phenotypically normal female presented with a fetus having a severe congenital heart defect with ventricular septal defect, tricuspid atresia, patent ductus arteriosus and interrupted aortic arch. The pregnant woman had a history of overall three consecutive aberrant pregnancies with tetralogy of Fallot. Standard G-banding karyotype analysis of the parents and the actual pregnancy were normal, while array comparative genomic hybridization (arrayCGH) analysis revealed a 22q11.2 microduplication within the fetus' genome. Fluorescence in situ hybridization (FISH) and short tandem repeat polymorphism (STRP) tests indicated the affected fetus inherited the interstitial 22q11.2 microduplication from the mother. High-resolution oligonucleotide microarray analysis showed this microduplication is located in the common 3 Mb 22q11.2 deletion region between positions 17.298 Mb and 20.246 Mb with a length of 2.948 Mb. This report demonstrates the remarkable intrafamilial variability of a 22q11.2 microduplication phenotype. The 22q11.2 microduplication carried by one of the healthy parents has most likely contributed to the recurrent fetal heart defects.European journal of medical genetics 04/2011; 54(4):e433-6. DOI:10.1016/j.ejmg.2011.03.009 · 1.49 Impact Factor