title: Fragile X syndrome without CCG amplification has an FMR1 deletion.
abstract: We describe a patient with typical clinical features of the fragile X syndrome, but without cytogenetic expression of the fragile X or an amplified CCG trinucleotide repeat fragment. The patient has a previously uncharacterized submicroscopic deletion encompassing the CCG repeat, the entire FMR1 gene and about 2.5 megabases of flanking sequences. This finding confirms that the fragile X phenotype can exist, without amplification of the CCG repeat or cytogenetic expression of the fragile X, and that fragile X syndrome is a genetically homogeneous disorder involving FMR1. We also found random X-inactivation in the mother of the patient who was shown to be a carrier of this deletion.
authors.affiliation: Department of Cytogenetics and Molecular Genetics, Adelaide Children's Hospital, South Australia.
authors.forename: A K
authors.initials: AK
authors.lastname: Gedeon
authors.forename: E
authors.initials: E
authors.lastname: Baker
authors.forename: H
authors.initials: H
authors.lastname: Robinson
authors.forename: M W
authors.initials: MW
authors.lastname: Partington
authors.forename: B
authors.initials: B
authors.lastname: Gross
authors.forename: A
authors.initials: A
authors.lastname: Manca
authors.forename: B
authors.initials: B
authors.lastname: Korn
authors.forename: A
authors.initials: A
authors.lastname: Poustka
authors.forename: S
authors.initials: S
authors.lastname: Yu
authors.forename: G R
authors.initials: GR
authors.lastname: Sutherland
mesh_terms: D000328:Adult; D001483:Base Sequence; D002478:Cells, Cultured; D002871:Chromosome Banding; D002874:Chromosome Mapping; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1; D005600:Fragile X Syndrome / Q000235:genetics*; D017353:Gene Deletion; D006801:Humans; D007621:Karyotyping; D008214:Lymphocytes / Q000502:physiology; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics*; D010375:Pedigree; D016601:RNA-Binding Proteins; D012091:Repetitive Sequences, Nucleic Acid; D014960:X Chromosome
chemical_list: D051860:Fragile X Messenger Ribonucleoprotein 1; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; C497683:FMR1 protein, human