title: Melorheostosis with ipsilateral nevus sebaceus (didymosis melorheosebacea).
abstract: We report an unusual case of unilateral melorheostosis and ipsilateral extensive sebaceous nevus. Because the two conditions affected the same side of the body, we hypothesize that they originated from a common genetic mechanism. The temporal and spatial co-occurrence may represent a further example of non-allelic didymosis (twin spotting). The embryo would carry two different recessive mutations at one gene locus or at linked loci on either of a pair of homologous chromosomes. Postzygotic recombination occurring during early embryonic development would result in two different populations of cells homozygous for either mutation. If this concept holds true, the present case may be described as " didymosis melorheosebacea ".
authors.affiliation: Institute of Medical Genetics, Charité Medical Centre, Humboldt University, Berlin, Germany. sigrid.tinschert@charite.de
authors.forename: Sigrid
authors.initials: S
authors.lastname: Tinschert
authors.forename: Anette
authors.initials: A
authors.lastname: Stein
authors.forename: Burkhard
authors.initials: B
authors.lastname: Göldner
authors.forename: Manfred
authors.initials: M
authors.lastname: Dietel
authors.forename: Rudolf
authors.initials: R
authors.lastname: Happle
mesh_terms: D000328:Adult; D001842:Bone and Bones / Q000000981:diagnostic imaging; D006222:Hamartoma / Q000150:complications* / Q000235:genetics / Q000473:pathology; D006801:Humans; D008297:Male; D008557:Melorheostosis / Q000150:complications* / Q000000981:diagnostic imaging / Q000235:genetics; D009154:Mutation; D011859:Radiography; D012871:Skin Diseases / Q000150:complications* / Q000235:genetics / Q000473:pathology