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Fragile X Syndrome MeSH Descriptor Data 2025


MeSH Heading
Fragile X Syndrome
Tree Number(s)
C10.597.606.360.455.500
C16.131.260.830.300
C16.320.180.830.300
C16.320.322.500.500
C16.320.400.525.500
Unique ID
D005600
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D005600
Scope Note
A condition characterized genotypically by mutation of the distal end of the long arm of the X chromosome (at gene loci FRAXA or FRAXE) and phenotypically by cognitive impairment, hyperactivity, SEIZURES, language delay, and enlargement of the ears, head, and testes. INTELLECTUAL DISABILITY occurs in nearly all males and roughly 50% of females with the full mutation of FRAXA. (From Menkes, Textbook of Child Neurology, 5th ed, p226)
Entry Term(s)
FRAXA Syndrome
FRAXE Syndrome
Fra(X) Syndrome
Fragile X Mental Retardation Syndrome
Fragile X-F Mental Retardation Syndrome
Mar (X) Syndrome
Marker X Syndrome
Martin-Bell Syndrome
Mental Retardation, X-Linked, Associated With Fragile Site Fraxe
Mental Retardation, X-Linked, Associated With Marxq28
X-Linked Mental Retardation and Macroorchidism
NLM Classification #
QS 677
Previous Indexing
Mental Retardation/genetics (1966-1982)
Sex Chromosomes (1968-1982)
X Chromosome (1978-1982)
See Also
Chromosome Fragile Sites
Chromosome Fragility
Intellectual Disability
Trinucleotide Repeat Expansion
Public MeSH Note
91; was see under SEX CHROMOSOME ABNORMALITIES 1983-90
History Note
91(83); was see under SEX CHROMOSOME ABNORMALITIES 1983-90
Date Established
1991/01/01
Date of Entry
1982/04/22
Revision Date
2018/06/30
Fragile X Syndrome Preferred
FRAXA Syndrome Narrower
FRAXE Syndrome Narrower
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