title: Use of repetitive DNA for diagnosis of chromosomal rearrangements.
abstract: We have used two repeated DNA fragments (3.4 and 2.1 kb) released from Y chromosome DNA by digestion with the restriction endonuclease Hae III to analyze potential Y chromosome/autosome translocations. Two female patients were studied who each had an abnormal chromosome 22 with extra quinacrine fluorescent material on the short arm. The origin of the 22p+ chromosomes was uncertain after standard cytologic examinations. Analysis of one patient's DNA with the Y-specific repeated DNA probes revealed the presence of both the 3.4 and 2.1kb Y-specific fragments. Thus, in this patient, the additional material was from the Y chromosome. Analysis of the second patient's DNA for Y-specific repeated DNA was negative, indicating that the extra chromosomal segment was not from the long arm of the Y chromosome. These two cases demonstrate that repeated DNA can distinguish between similar appearing aberrant chromosomes and may be useful in karyotypic and prenatal diagnosis.
mesh_terms: D000328:Adult; D001483:Base Sequence; D002871:Chromosome Banding; D002904:Chromosomes, Human, 21-22 and Y; D004247:DNA / Q000032:analysis; D004262:DNA Restriction Enzymes; D015252:Deoxyribonucleases, Type II Site-Specific; D005260:Female; D006801:Humans; D007621:Karyotyping; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012091:Repetitive Sequences, Nucleic Acid; D014178:Translocation, Genetic; D014998:Y Chromosome
chemical_list: D004247:DNA; D004262:DNA Restriction Enzymes; D015252:Deoxyribonucleases, Type II Site-Specific; C024403:GGCC-specific type II deoxyribonucleases