title: Frequency of the fragile X syndrome in Chinese mentally retarded populations is similar to that in Caucasians.
abstract: Fragile X syndrome is recognized as the most common inherited cause of mental retardation in western countries. The prevalence of the fragile X syndrome in Asian populations is uncertain. We report a multi-institutional collaborative study of molecular screening for the fragile X syndrome from 1,127 Chinese mentally retarded (MR) individuals. We found that 2.8% of the Chinese MR population screened by DNA analysis had the fragile X full mutation. Our screening indicated that the fragile X syndrome prevalence was very close to that of Caucasian subjects. In addition, we found that 62.5% of fragile X chromosomes had a single haplotype for DXS548-FRAXAC1 (21-18 repeats) which was present in only 9.7% of controls. This unique distribution of microsatellite markers flanking the FMR1 CGG repeats suggests that the fragile X syndrome in Chinese populations, as in the Caucasian, may also be derived from founder chromosomes.
authors.affiliation: Department of Human Genetics, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA. omrddzhong@aol.com
authors.forename: N
authors.initials: N
authors.lastname: Zhong
authors.forename: W
authors.initials: W
authors.lastname: Ju
authors.forename: W
authors.initials: W
authors.lastname: Xu
authors.forename: L
authors.initials: L
authors.lastname: Ye
authors.forename: Y
authors.initials: Y
authors.lastname: Shen
authors.forename: G
authors.initials: G
authors.lastname: Wu
authors.forename: S H
authors.initials: SH
authors.lastname: Chen
authors.forename: R
authors.initials: R
authors.lastname: Jin
authors.forename: X F
authors.initials: XF
authors.lastname: Hu
authors.forename: A
authors.initials: A
authors.lastname: Yang
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: P
authors.initials: P
authors.lastname: Poon
authors.forename: C
authors.initials: C
authors.lastname: Pang
authors.forename: Y
authors.initials: Y
authors.lastname: Zheng
authors.forename: L
authors.initials: L
authors.lastname: Song
authors.forename: P
authors.initials: P
authors.lastname: Zhao
authors.forename: B
authors.initials: B
authors.lastname: Fu
authors.forename: H
authors.initials: H
authors.lastname: Gu
authors.forename: W T
authors.initials: WT
authors.lastname: Brown
mesh_terms: D000483:Alleles; D002681:China / Q000453:epidemiology; D005260:Female; D018703:Founder Effect; D005600:Fragile X Syndrome / Q000453:epidemiology* / Q000235:genetics*; D005820:Genetic Testing; D006239:Haplotypes; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology* / Q000235:genetics*; D008297:Male; D044465:White People; D014960:X Chromosome / Q000235:genetics