title: Pallister-Killian syndrome in a girl with mild developmental delay and mosaicism for hexasomy 12p.
abstract: We report on a 5-year-old girl with Pallister-Killian syndrome (OMIM #601803) due to mosaicism of two supernumerary isochromosomes (hexasomy 12p). Hexasomy 12p was found in 20% of the cells by chromosome analysis of cultured skin fibroblasts and confirmed by FISH- and arrayCGH analysis. The girl has woolly and sparse hair, absence of lateral eyebrows, dry skin, brittle nails, hypopigmented patches, frontal bossing, hearing loss, hypertrophic dilated cardiomyopathy, polydactyly, and mild developmental delay. This is the second live case of mosaicism for hexasomy 12p to be reported. A gene-dosage hypothesis has previously suggested that cases with hexasomy 12p would have a worse phenotype than cases with tetrasomy 12p. The relatively mild symptoms found in the current girl with hexasomy 12p may to contradict this hypothesis.
authors.affiliation: Department of Clinical Genetics, Aarhus University Hospital, Aarhus C, Denmark. idavogel@dadlnet.dk
authors.forename: Ida
authors.initials: I
authors.lastname: Vogel
authors.forename: Troels
authors.initials: T
authors.lastname: Lyngbye
authors.forename: Alice
authors.initials: A
authors.lastname: Nielsen
authors.forename: Søren
authors.initials: S
authors.lastname: Pedersen
authors.forename: Jens Michael
authors.initials: JM
authors.lastname: Hertz
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000235:genetics; D000649:Amniocentesis; D002869:Chromosome Aberrations; D025063:Chromosome Disorders / Q000235:genetics*; D022202:Chromosomes, Artificial, Bacterial; D002881:Chromosomes, Human, Pair 12; D055028:Comparative Genomic Hybridization; D020732:Cytogenetic Analysis; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D002658:Developmental Disabilities / Q000235:genetics*; D005260:Female; D018628:Gene Dosage; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007621:Karyotyping; D009030:Mosaicism; D020966:Muscular Disorders, Atrophic / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis
chemical_list: D004247:DNA