title: Mental retardation locus in Xp21 chromosome microdeletion.
abstract: Xp21 microdeletion syndrome is associated with variable size Xp21 deletions that usually include the glycerol kinase locus. The clinical phenotypes we studied in this chromosome region include: Xpter - Aland Island eye disease (AIED) -adrenal hypoplasia (AH) -glycerol kinase (GKD) -Duchenne muscular dystrophy (DMD) -retinitis pigmentosa (RP) -ornithine transcarbamylase (OTC) -centromere. In a compilation of 18 individuals in 14 families with the AH, GKD, and DMD loci deleted, 17 were male and all were developmentally delayed. In contrast, we report mentally retarded female carriers in two Xp21 deletion syndrome families with DMD, GKD, and AH in affected males. In the first family with normal karyotypes, a submicroscopic deletion was associated with DMD in the retarded male and with retardation in carrier females. In the second family an X chromosome with a cytogenetically deleted Xp21 distal to the OTC and RP genes segregated in the affected male and retarded female carriers. DNA analysis at the DMD locus verified the cytogenetic findings. This report of mental retardation in otherwise asymptomatic female carriers of Xp21 deletion classifies one form of mental retardation in females.
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Science, University of California, San Francisco 94143-0720.
authors.forename: M H
authors.initials: MH
authors.lastname: Fries
authors.forename: R V
authors.initials: RV
authors.lastname: Lebo
authors.forename: S A
authors.initials: SA
authors.lastname: Schonberg
authors.forename: M
authors.initials: M
authors.lastname: Golabi
authors.forename: W K
authors.initials: WK
authors.lastname: Seltzer
authors.forename: S E
authors.initials: SE
authors.lastname: Gitelman
authors.forename: M S
authors.initials: MS
authors.lastname: Golbus
mesh_terms: D000311:Adrenal Glands / Q000002:abnormalities; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D005260:Female; D005991:Glycerol Kinase / Q000172:deficiency / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009136:Muscular Dystrophies / Q000235:genetics*; D010375:Pedigree; D014960:X Chromosome
chemical_list: D005991:Glycerol Kinase