Mechanisms and consequences of small supernumerary marker chromosomes: from Barbara McClintock to modern genetic-counseling issues.

ABSTRACT: Supernumerary marker chromosomes (SMCs) are common, but their molecular content and mechanism of origin are often not precisely characterized. We analyzed all centromere regions to identify the junction between the unique chromosome arm and the pericentromeric repeats. A molecular-ruler clone panel for each chromosome arm was developed and used for the design of a custom oligonucleotide array. Of 27 nonsatellited SMCs analyzed by array comparative genomic hybridization (aCGH) and/or fluorescence in situ hybridization (FISH), seven (approximately 26%) were shown to be unique sequence negative. Of the 20 unique-sequence-positive SMCs, the average unique DNA content was approximately 6.5 Mb (range 0.3-22.2 Mb) and 33 known genes (range 0-149). Of the 14 informative nonacrocentric SMCs, five (

SUBMITTER: Baldwin EL 

PROVIDER: S-EPMC2427313 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature