title: Effect of the deficits of fragile X mental retardation protein on cognitive status of fragile x males and females assessed by robust pedigree analysis.
abstract: The effect of the fragile X mental retardation 1 (FMR1) gene product (fragile X mental retardation protein [FMRP]) deficits on Full-Scale IQ (FSIQ) and FSIQ-adjusted Wechsler subtests and index scores in fragile X disorder were assessed using a robust modification of the maximum likelihood estimators for pedigree data. The results from 144 extended families have demonstrated a linear effect of progressively reduced levels of FMRP on the FSIQ and all subtest and summary scores in either gender. The effect of FMRP in decreasing FSIQ-adjusted subtest scores was highly significant for Digit Span, Symbol Search, Object Assembly, and Picture Arrangement, with a consistent trend in both genders. Heritability for FSIQ and unadjusted subtest scores estimated from the covariance model did not exceed 50% and varied widely from the highest for Verbal score to the lowest for Picture Completion score. Possible mechanisms by which FMRP deficit impacts on specific weaknesses in fragile X are considered on the basis of present data.
authors.affiliation: School of Psychological Science, La Trobe University, Melbourne. d. loesch@latrobe.edu.au
authors.forename: Danuta Z
authors.initials: DZ
authors.lastname: Loesch
authors.forename: Richard M
authors.initials: RM
authors.lastname: Huggins
authors.forename: Quang M
authors.initials: QM
authors.lastname: Bui
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Epstein
authors.forename: Annette K
authors.initials: AK
authors.lastname: Taylor
authors.forename: Randi Jensen
authors.initials: RJ
authors.lastname: Hagerman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000175:diagnosis; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1; D005600:Fragile X Syndrome / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009419:Nerve Tissue Proteins / Q000235:genetics*; D010375:Pedigree; D016601:RNA-Binding Proteins; D014888:Wechsler Scales
chemical_list: D051860:Fragile X Messenger Ribonucleoprotein 1; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; C497683:FMR1 protein, human