title: Is there a yet unreported unbalanced chromosomal abnormality without phenotypic consequences in proximal 4p?
abstract: Unbalanced chromosomal abnormalities (UBCA) are reported for >50 euchromatic regions of almost all human autosomes. UBCA are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. Here we report on a partial trisomy of chromosome 4 of the centromere-near region of the short arm of chromosome 4 present as a small supernumerary marker chromosome (sSMC). The sSMC was present in >70% of amnion cells and in 60% of placenta. Further delineation of the size of the duplicated region was done by molecular cytogenetics and array comparative genomic hybridization. Even though the sSMC lead to a partial trisomy of ~9 megabase pairs, a healthy child was born, developing normally at 1 year of age. No comparable cases are available in the literature. Thus, we discuss here the possibility of having found a yet unrecognized chromosomal region subject to UBCA.
authors.affiliation: Jena University Hospital, Institute of Human Genetics, Kollegiengasse 10, Jena, Germany. i8lith@mti.uni-jena.de
authors.forename: T
authors.initials: T
authors.lastname: Liehr
authors.forename: I
authors.initials: I
authors.lastname: Bartels
authors.forename: B
authors.initials: B
authors.lastname: Zoll
authors.forename: E
authors.initials: E
authors.lastname: Ewers
authors.forename: K
authors.initials: K
authors.lastname: Mrasek
authors.forename: N
authors.initials: N
authors.lastname: Kosyakova
authors.forename: M
authors.initials: M
authors.lastname: Merkas
authors.forename: A B
authors.initials: AB
authors.lastname: Hamid
authors.forename: F
authors.initials: F
authors.lastname: von Eggeling
authors.forename: N
authors.initials: N
authors.lastname: Posorski
authors.forename: A
authors.initials: A
authors.lastname: Weise
mesh_terms: D002869:Chromosome Aberrations; D002894:Chromosomes, Human, Pair 4; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping