Introduction: Fragile X syndrome (FXS) is one of the most prevalent genetic causes of developmental disability, representing the most frequent form of inherited severe cognitive deficit. The present study was undertaken to investigate FXS and its prevalence in moderate mentally retarded people in patients. Materials and methods: Nineteen people with moderate mental retardation (MR) who wer...

Numerical solutions for Sommerfeld model in nonrelativistic case are presented for the scattering of a spinless extended charged body in a static Coulomb field of a fixed point charge. It is shown that differential cross section for extended body preserves the form of the Rutherford result with multiplier, not equal to one (as in classical case), but depending on the size of Sommerfeld particle...

A survey of the mentally retarded children with an IQ between 30 and 55 born in a 10-year period (1955-64) and now of school age was carried out in New South Wales. The number of propositi who had a similarly affected sib of the same sex was ascertained; 58 boys had a similarly affected brother(s) and 22 girls had a similarly affected sister(s). It is suggested that the excess of affected broth...

because of its prevalence (ca. 2%), the few therapeutic options that are currently available, and the resulting life-long harm to the affected persons, their families, and society as a whole (1). Persons with an intelligence quotient (IQ) below 70 are considered mentally retarded; milder forms of mental retardation, with IQ between 50 and 70 (overall prevalence ca. 1.5%), are more common than m...

Familial patterns of mental retardation were examined among white and black children in the NINCDS Collaborative Perinatal Project population. Among whites, the mildly retarded children had more affected relatives than did the severely retarded, consistent with the traditional two-group theory of mental retardation. In blacks, where differences in family patterns between the mildly and the seve...

One hundred and eighty three children suffering from mental retardation were studied over a period of 17 months (December’80 April’82). Mental retardation in 101 cases (5 5.2%) was due to preventable causes i.e. tubercular meningitis, birth trauma, encephalitis, cretinism and kernicterus. Majority of them belonged to lower socio-economic group and had no access to medical facilities, therefore ...