title: Variants of chromosome 9 with additional euchromatic bands: two case reports.
abstract: This paper documents a prenatal case of maternally inherited subtle duplication of chromosome 9 bands q21.1 to q21.2 and a second case with two G-bands within the 9qh region. Cytogenetic studies of these cases included G-banding, C-banding, fluorescent in situ hybridization (FISH) using chromosome 9 specific library probe, and the classical satellite probe. In both patients, the additional bands were G-bands and C-band negative. By FISH studies they were negative for the satellite heterochromatin probe and positive for the chromosome 9 painting probe. Therefore, the extra bands were presumably euchromatin and part of chromosome 9. The chromosome 9 variants and their possible mechanisms of origin are discussed.
authors.affiliation: Cytogenetics Laboratory, Corning Nichols Institute, San Juan Capistrano, California 92690-6130, USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Reddy
mesh_terms: D000328:Adult; D002675:Child, Preschool; D002869:Chromosome Aberrations / Q000235:genetics*; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence