A microdeletion syndrome is a syndrome caused by a chromosomal
deletion
Deletion or delete may refer to:
Computing
* File deletion, a way of removing a file from a computer's file system
* Code cleanup, a way of removing unnecessary variables, data structures, cookies, and temporary files in a programming language
* ...
smaller than 5 million
base pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...
s (5 Mb) spanning several genes that is too small to be detected by conventional cytogenetic methods or high resolution karyotyping (2–5 Mb).
Detection is done by
fluorescence in situ hybridization (FISH). Larger
chromosomal deletion syndromes are detectable using
karyotyping techniques.
Examples
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DiGeorge syndrome or velocardiofacial syndrome – most common microdeletion syndrome
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Prader–Willi syndrome
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Angelman syndrome
Angelman syndrome or Angelman's syndrome (AS) is a genetic disorder that mainly affects the nervous system. Symptoms include a small head and a specific facial appearance, severe intellectual disability, developmental disability, limited to no f ...
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Neurofibromatosis type I
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Neurofibromatosis type II
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Williams syndrome
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Miller–Dieker syndrome
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Smith–Magenis syndrome
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Rubinstein–Taybi syndrome
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Wolf–Hirschhorn syndrome
References
Further reading
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Microdeletions and Molecular GeneticsMicrodeletion syndromes (chromosomes 1 to 11)on UpToDate
List of 100 microdeletion/duplication syndromes detected by array-CGH on GENOMA
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13 chromosomal disorders you may not have heard of
{{Chromosomal abnormalities
Autosomal monosomies and deletions
Syndromes