title: Mucopolysaccharidosis type II in a female patient with a reciprocal X;9 translocation and skewed X chromosome inactivation.
abstract: Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a rare X-linked disorder caused by deficient activity of the lysosomal enzyme, iduronate-2-sulfatase (IDS). Phenotypic expression of MPS II in female patients rarely occurs and may be the result of (i) structural abnormalities of the X chromosome, (ii) homozygosity for disease-causing mutations, or (iii) skewed X-chromosome inactivation, in which the normal IDS allele is preferentially inactivated and the abnormal IDS allele is active. We report here on a female patient with clinical MPS II manifestations, deficiency of IDS enzyme activity and a de novo balanced reciprocal X;9 translocation. As our patient has a skewed XCI pattern, but neither genomic IDS mutations nor abnormal IDS transcripts were detected, we speculate about the possible role of the chromosomal rearrangement in reducing the IDS translation efficiency.
authors.affiliation: U.O.C. di Genetica Medica, A.O.R.N. "G. Rummo", Benevento, Italy.
authors.forename: Fortunato
authors.initials: F
authors.lastname: Lonardo
authors.forename: Paola
authors.initials: P
authors.lastname: Di Natale
authors.forename: Susanna
authors.initials: S
authors.lastname: Lualdi
authors.forename: Fabio
authors.initials: F
authors.lastname: Acquaviva
authors.forename: Cristina
authors.initials: C
authors.lastname: Cuoco
authors.forename: Francesca
authors.initials: F
authors.lastname: Scarano
authors.forename: Marianna
authors.initials: M
authors.lastname: Maioli
authors.forename: Luigi Michele
authors.initials: LM
authors.lastname: Pavone
authors.forename: Grazia
authors.initials: G
authors.lastname: Di Gregorio
authors.forename: Mirella
authors.initials: M
authors.lastname: Filocamo
authors.forename: Gioacchino
authors.initials: G
authors.lastname: Scarano
mesh_terms: D000483:Alleles; D002648:Child; D005260:Female; D006801:Humans; D007066:Iduronate Sulfatase / Q000235:genetics; D016532:Mucopolysaccharidosis II / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D014178:Translocation, Genetic / Q000235:genetics*; D049951:X Chromosome Inactivation / Q000235:genetics*
chemical_list: D007066:Iduronate Sulfatase
keywords: X chromosome inactivation; X;autosome translocation; female Hunter syndrome; iduronate 2-sulfatase; mucopolysaccharidosis type II; skewed