Fragile sites /Chromosomal aberrations play a role in the etiology of mental retardation and other associated complications. Since Down syndrome is the most common genetic cause of mental retardation, the present study was done to evaluate the effect of fragile sites on sys-temic diseases and growth and developmental pattern among them. Human lymphocyte cell culture with folate free medium show...

Genetic recombination near the fragile X locus (Xq27.3) has frequently been a problem in linkage studies of families in which the fragile X is segregating. This case report illustrates the resolution of a difficult situation in a fragile X family for whom cytogenetic studies were inconclusive and where recombination had twice confounded attempts at prenatal DNA diagnosis by RFLP analysis. Using...

Aphidicolin-induced common fragile sites are site-specific gaps or breaks seen on metaphase chromosomes after partial inhibition of DNA synthesis. These fragile sites were first recognized during the early studies of the fragile X syndrome and are induced by the same conditions of folate or thymidylate stress used to induce the fragile X site. Common fragile sites are normally stable in culture...

The common fragile site, FRA3B, has been shown to be a site of frequent homozygous deletions in some cancers, resulting in loss of expression of the associated FHIT gene. It has been proposed that FHIT is a tumor suppressor gene that is inactivated as a result of the instability of FRA3B in tumorigenesis. More recently, deletions at other common fragile sites, FRA7G and FRA16D, have been identi...

The fragile X chromosome, associated with a common form of X-linked mental retardation, is cytologically observed most often as a gap or fragile site near the distal end of the long arm in band Xq28. Expression of this site is variable and dependent upon lowered thymidylate pools. In order to examine the behavior of this fragile site in a foreign genetic background, interspecific somatic cell h...

The international donor community has grave concerns about the prospects for poverty reduction in what it terms fragile states. A state is classified as fragile if its country policy and institutional assessment (CPIA) score falls below a particular threshold. Recognizing that all states are fragile to varying degrees, this paper questions the method used by the international community to deem ...

The international donor community has grave concerns about the prospects for poverty reduction in what it terms fragile states. A state is classified as fragile if its country policy and institutional assessment (CPIA) score falls below a particular threshold. Recognizing that all states are fragile to varying degrees, this paper questions the method used by the international community to deem ...

Cyanophyta of some paddy-fields of Golestan province (North of Iran, near the Caspian Sea) have been studied during 2006–07. Phormidium subinerusatum, P. tenue, P. jadinianum, P. purpurascens, P. lucidum, P. fragile, Microcoleus palaodus, M. lacustris are new records for Golestan province and Iran. Results showed that  P. subinerusatum, P. tenue were dominant in all stations. P. fragile, in spr...