Network‐based analysis using chromosomal microdeletion syndromes as a model

Microscopic forms of karyotyping and cytogenetic analysis by means of G-banded chromosome analysis and rapid FISH (fluorescencein situhybridization) on amniotic fluids or chorionic villus samples are at present regarded as the gold standard for prenatal diagnosis of chromosomal anomalies. Nevertheless, up to now the resolution of conventional chromosomal analysis was limited to approximately 4–5 Mb and not smaller than 2 Mb for FISH. Thus numerous common microdeletion syndromes are not detectable by conventional karyotyping. In addition, prenatal cells yield lower band resolution by conventional karyotyping than peripheral white blood cells making detection of subtle abnormalities even more difficult. With the advances in molecular-based techniques, a collaborative effort has led to the standardized method for detection of a restricted set of common chromosomal aneuploidies and microdeletion syndromes such as Down's syndrome, DiGeorge or Angelman syndrome either by rapid FISH and/or quantitative fluorescent PCR (QF-PCR). Even if the presence of particular phenotypic features of microdeletion or duplication syndromes may direct the use of syndrome-specific FISH tests in the postnatal period, syndrome-specific FISH analysis still has a very limited potential and application in the prenatal period due to the limitation in prenatal morphological or imaging diagnosis of many of the syndromes.

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Microdeletion syndromes and psychiatry: An update

BJPsych Advances ◽

10.1192/apt.bp.114.012864 ◽

2017 ◽

Vol 23 (3) ◽

pp. 149-157

Author(s):

Melvyn W. B. Zhang ◽

Nikki Fong ◽

Ying Hui Quek ◽

Cyrus S. H. Ho ◽

Beng Yeong Ng ◽

...

Keyword(s):

Intellectual Disability ◽

Digeorge Syndrome ◽

Chromosomal Abnormalities ◽

Psychiatric Symptoms ◽

Treatment Options ◽

Daily Practice ◽

Learning Objectives ◽

Prader Willi Syndrome ◽

Microdeletion Syndrome ◽

Microdeletion Syndromes

SummaryMicrodeletion syndrome is an important topic in intellectual disability, associated with various psychiatric symptoms, such as autism, attention deficit, hyperactivity, obsession and compulsion, and psychosis. In this article, we provide a clinical update on the following syndromes and their associated psychiatric disorders: Prader–Willi syndrome, Angelman syndrome, Williams syndrome, Wolf–Hirschhorn syndrome, cri du chat syndrome, DiGeorge syndrome and Rubinstein–Taybi syndrome.Learning Objectives• Gain an up-to-date understanding of the microdeletion syndromes commonly seen in daily practice• Appreciate the association between underlying chromosomal abnormalities and the resultant intellectual disabilities in microdeletion syndromes• Gain up-to-date knowledge about the treatment options for the various microdeletion syndromes commonly seen in daily practice

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Rapid and Inexpensive Screening of Genomic Copy Number Variations Using a Novel Quantitative Fluorescent PCR Method

Disease Markers ◽

10.1155/2013/704917 ◽

2013 ◽

Vol 35 ◽

pp. 589-594

Author(s):

Martin Stofanko ◽

Joan C. Han ◽

Sarah H. Elsea ◽

Heloísa B. Pena ◽

Higgor Gonçalves-Dornelas ◽

...

Keyword(s):

Low Cost ◽

Dna Amplification ◽

Copy Number Variations ◽

Public Healthcare ◽

Microdeletion Syndromes ◽

Fluorescent Pcr ◽

Significant Burden ◽

And Performance ◽

And Control ◽

Quantitative Fluorescent Pcr

Detection of human microdeletion and microduplication syndromes poses significant burden on public healthcare systems in developing countries. With genome-wide diagnostic assays frequently inaccessible, targeted low-cost PCR-based approaches are preferred. However, their reproducibility depends on equally efficient amplification using a number of target and control primers. To address this, the recently described technique called Microdeletion/Microduplication Quantitative Fluorescent PCR (MQF-PCR) was shown to reliably detect four human syndromes by quantifying DNA amplification in an internally controlled PCR reaction. Here, we confirm its utility in the detection of eight human microdeletion syndromes, including the more common WAGR, Smith-Magenis, and Potocki-Lupski syndromes with 100% sensitivity and 100% specificity. We present selection, design, and performance evaluation of detection primers using variety of approaches. We conclude that MQF-PCR is an easily adaptable method for detection of human pathological chromosomal aberrations.

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