title: Cryptic x; autosome translocation in a boy--delineation of the phenotype.
abstract: Chromosome X-to-autosome translocations [t(X;A)] are rare rearrangements with an estimated occurrence of 1 to 3 per 10,000 live births. Occurrences of Xq duplications have been observed in male and female subjects in whom the X chromosome segment escapes inactivation and results in functional disomy. We report a case of X;6 translocation in a 7-year-old boy with severe mental retardation, hypotonia, and recurrent respiratory tract infections. High-resolution chromosome analyses (fluorescence in situ hybridization, multiplex ligation probe-dependent amplification, and whole-genome array) revealed a terminal duplication of chromosome X at q28-qter (approximately 3.246 Mb in size) involving gene MECP2 and a terminal deletion (approximately 1.89 Mb) with the breakpoint at 6q27. This is the second report of a boy with a cryptic unbalanced Xq-autosome translocation. This case increases our understanding of mental disability caused by terminal Xq duplication.
authors.affiliation: Department of Medical Genetics, The Children's Memorial Health Institute, Aleja Dzieci Polskich 20, 04-736 Warsaw, Poland. jezela@gmail.com
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Jezela-Stanek
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Ciara
authors.forename: Marzena
authors.initials: M
authors.lastname: Juszczak
authors.forename: Magdalena
authors.initials: M
authors.lastname: Pelc
authors.forename: Anna
authors.initials: A
authors.lastname: Materna-Kiryluk
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Krajewska-Walasek
mesh_terms: D002648:Child; D041321:Chromosomes, Human, X / Q000235:genetics; D017353:Gene Deletion; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology* / Q000235:genetics; D008297:Male; D051783:Methyl-CpG-Binding Protein 2 / Q000235:genetics; D009123:Muscle Hypotonia / Q000209:etiology / Q000235:genetics; D010641:Phenotype; D012141:Respiratory Tract Infections / Q000209:etiology / Q000235:genetics; D012729:Sex Chromosome Aberrations; D025064:Sex Chromosome Disorders / Q000150:complications / Q000235:genetics / Q000473:pathology; D014178:Translocation, Genetic / Q000235:genetics*; D014314:Trisomy / Q000235:genetics / Q000473:pathology
chemical_list: C497392:MECP2 protein, human; D051783:Methyl-CpG-Binding Protein 2