Three families with high expression of a fragile site at Xq27.3, lack of anomalies at the FMR-1 CpG island, and no clear phenotypic association.

Abstract excerpt

We report on 3 families where the presence and segregation at high frequency of a fragile Xq27.3 site is not associated with the mutations and methylation anomalies typically seen in the fragile X [Fra(X)] syndrome. In one family, a folate insensitive fragile site was associated with Robin sequence in the propositus. In a second family a fra(X) negative mother has two fra(X) positive sons (one mentally retarded...

Topics

• Chromosome Fragile Sites
• Chromosome Fragility
• Female
• Fragile X Syndrome
• Gene Expression
• Humans
• Intellectual Disability
• Male
• Methylation
• Pedigree
• Phenotype