Fragile X mutation and FG syndrome-like phenotype.

Abstract

We present data on 4 mentally retarded brothers, 2 of whom were dizygotic twins with congenital hypotonia, constipation, head size disproportionately large for length or height, and a combination of minor anomalies suggestive of FG syndrome. These brothers have a mentally retarded full sister with similar minor anomalies and an older half-brother with the Martin-Bell syndrome. The mother is mentally retarded; 4 of 7 individuals are positive for fragile X, but all have a CGG expansion ranging from 0.2-2 to 4 kb. Although the phenotype is not completely typical of the FG syndrome and the coincidence of the FMR1 mutation and segregation of the MCA/MR phenotype are highly unlikely, the FMR1 mutation may affect morphogenesis more extensively and differently than the Martin-Bell syndrome does to effect an FG syndromelike phenotype in certain families. This phenotype does not appear to be a contiguous gene syndrome, but an effect of the FMR1 mutation on an adjacent gene must be considered.

• Authors: C Piussan, M Mathieu, P Berquin, J P Fryns
• Journal: American journal of medical genetics (Am J Med Genet) Vol. 64 Issue 2 Pg. 395-8 (Aug 09 1996) ISSN: 0148-7299 [Print] United States
• PMID: 8844090 (Publication Type: Case Reports, Journal Article)

Chemical References

• FMR1 protein, human
• Nerve Tissue Proteins
• RNA-Binding Proteins
• Fragile X Mental Retardation Protein

Topics

• Child
• Diseases in Twins
• Female
• Fragile X Mental Retardation Protein
• Fragile X Syndrome (genetics)
• Humans
• Infant
• Intellectual Disability (genetics)
• Male
• Morphogenesis
• Nerve Tissue Proteins (genetics)
• Pedigree
• Phenotype
• RNA-Binding Proteins
• Sex Chromosome Aberrations (genetics)
• Syndrome
• Trinucleotide Repeats