The study of common fragile sites has its roots in the early cytogenetic investigations of the fragile X syndrome. Long considered an interesting component of chromosome structure, common fragile sites have taken on novel significance as regions of the genome that are particularly sensitive to certain forms of replication stress, which are frequently rearranged in cancer cells. In recent years,...

DNA sequences have been located at the fragile X site by in situ hybridization and by the mapping of breakpoints in two somatic cell hybrids that were constructed to break at the fragile site. These hybrids were found to have breakpoints in a common 5-kilobase Eco RI restriction fragment. When this fragment was used as a probe on the chromosomal DNA of normal and fragile X genotype individuals,...

BACKGROUND Fragile skin is a poorly understood skin condition, particularly in the general adult population. There are currently limited epidemiological data on the prevalence of fragile skin in adults. The objectives of this study were to assess the prevalence of perceived fragile skin across different skin types in representative samples of the general adult populations in Mexico and Russia, ...

Fragile sites consist of isochromatid chromosome breaks which take place at specific sites along a chromosome and segregate as simple Mendelian traits.1 2 While the Xq28 fragile site is regarded as a marker for X linked mental retardation, the fragile sites on autosomes are regarded as normal uncommon variants. The present case supports the idea that the presence of fragile sites may constitute...

Females with fragile X syndrome, the most common form of inherited developmental and learning problems, are known to be impaired in executive function. The current study is the first to investigate the performance of females with fragile X on a cognitive interference task utilizing functional magnetic resonance imaging (fMRI). Fourteen females with fragile X and 14 age-matched healthy controls ...

Common fragile sites are loci that form chromosome gaps or breaks when DNA synthesis is partially inhibited. Fragile sites are prone to deletions, translocations, and other rearrangements that can cause the inactivation of associated tumor suppressor genes in cancer cells. It was previously shown that ATR is critical to fragile-site stability and that ATR-deficient cells have greatly elevated f...

The utility of the pfxa3 probe for direct molecular diagnosis of the fragile X (FRAXA) has been established. This probe detects amplification of an unstable DNA element consisting of variable length CCG repeats. The size of the amplified fragment is correlated with phenotype and was determined using PstI digested DNA in family members. In 35 families with the fragile X, there was correspondence...

It has been suggested that delayed DNA replication underlies fragility at common human fragile sites, but specific sequences responsible for expression of these inducible fragile sites have not been identified. One approach to identify such cis-acting sequences within the large nonexonic regions of fragile sites would be to identify conserved functional elements within orthologous fragile sites...

background: fragile histidine triad protein (fhit), as a known tumor suppressor protein, has been proposed to play crucial role in inhibiting p53 degradation by mdm2. studies have confirmed fhit interaction with p53 or mdm2, although functional interacting domains of fhit with mdm2 and/or p53 are not completely defined. thus, through determining the significant structural interacting domains of...

It has been suggested that delayed DNA replication underlies fragility at common human fragile sites, but specific sequences responsible for expression of these inducible fragile sites have not been identified. One approach to identify such cis-acting sequences within the large nonexonic regions of fragile sites would be to identify conserved functional elements within orthologous fragile sites...