Fragile X syndrome (FXS), a single gene disorder with an expanded CGG allele on the X chromosome, is the most common form of inherited cognitive impairment. The cognitive deficit ranges from mild learning disabilities to severe intellectual disability. The phenotype includes hyperactivity, short ...
fragile X syndrome n. An inherited disorder caused by a defective gene on the X chromosome and marked by intellectual disability, developmental disorders, enlarged testes, and facial abnormalities in males and by mild or no effects in heterozygous females. ...
Fragile X syndrome (FXS), or Martin-Bell syndrome, is a non-Mendelian trinucleotide repeat disorder. FXS is the most prevalent inherited cause of mild-to-severe intellectual disability and the most common monogenic cause of autism spectrum disorder. It accounts for about one-half of cases of X...
Fragile X syndrome(FXS) is an X-linkedgeneticdisorder characterized by a mild-to-moderate form of mental retardation and learning disability. It is caused by a CGG repeat expansion in the 5'untranslated region(UTR) of theFMR1gene, which leads to transcriptional silencing of the gene viaDNA meth...
Fragile X syndrome, also termed Martin-Bell syndrome or marker X syndrome, is the most common cause of inherited intellectual disability and autism and is the second most common cause of genetically associated mental deficiencies, after trisomy 21. Conservative estimates are that fragile X syndrome ...
Fragile X Syndrome - Learn about the causes, symptoms, diagnosis & treatment from the Merck Manuals - Medical Consumer Version.
Fragile X syndrome is caused by mutations in the FMR1 gene on the X chromosome, which prevent the gene's expression. This absence of the FMR1-encoded protein during brain development has been shown to cause the over-excitability in neurons associated with the syndrome. Now, for the first ...
By the age of 3 years, most males will test in the mentally retarded range.66 Ultimately, almost all males with the fragile X syndrome are mentally retarded, with severity ranging from profound (IQ Ͻ20) to mild mental retardation (IQ 50 –70), with most being moderately retarded (IQ ...
syndrome includes a long face with prominent forehead, large ears, and prominent jaw and macro-orchidism. There is a growing understanding of the implications for some premutation carriers, including mild developmental delay, premature ovarian failure, or fragile X-associated tremor/ataxia syndrome.[2...
Recent data from a national survey highlighted a significant difference in obesity rates in young fragile X males (31%) compared to age matched controls (18%). Fragile X syndrome (FXS) is the most common cause of intellectual disability in males and the most common single gene cause of autis...