Fluorescence in situ hybridization (FISH) of a whole-arm translocation involving chromosomes 18 and 20 with alpha-satellite DNA probes: detection of a centromeric DNA break?
Fluorescence in situ hybridization (FISH) with alpha-satellite DNA probes was used to study whole-arm chromosome translocation products in a family in which the propositus was shown to have a monosomy 18p/trisomy 20p imbalance. By this approach, we show that the chromosome 18 alpha-satellite DNA block is split into 2 smaller units, whereas the chromosome 20 breakpoint is not included within the alpha-satellite DNA region. We found no evidence to suggest that this split alpha-satellite DNA region has reduced or impaired the function of the centromere or that it contributed to the phenotype of the propositus. The FISH technique critically demonstrated the involvement of a whole-arm translocation in this case and provided accurate identification of breakpoints, which was not possible with standard banding techniques.
Cantú
E S
ES
Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston 29425.
Khan
T A
TA
Pai
G S
GS
D000015:Abnormalities, Multiple / Q000235:genetics*; D002503:Centromere / Q000648:ultrastructure*; D002887:Chromosomes, Human, Pair 18; D002890:Chromosomes, Human, Pair 20; D015342:DNA Probes; D004276:DNA, Satellite; D004303:Dosage Compensation, Genetic; D005145:Face / Q000002:abnormalities; D005183:Failure to Thrive / Q000235:genetics; D006330:Heart Defects, Congenital / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007231:Infant, Newborn; D008297:Male; D014178:Translocation, Genetic
D015342:DNA Probes; D004276:DNA, Satellite