Jumping translocation with partial duplications and triplications of chromosomes 7 and 15.

We report a 2-year-old female with seizures, mild dysmorphic features and a jumping translocation involving chromosome 15 that results in multiple cell lines with partial duplications and triplications of chromosomes 7 and 15. Fluorescent in situ hybridization (FISH) and chromosome microdissection were used to identify the complex nature of the jumping translocation. Interstitial telomeres were observed at the jumping translocation sites. The jumping chromosome rearrangement was also found to have a partial duplication of 7p as demonstrated by chromosome microdissection. Despite these partial duplications and triplications of chromosomes 7 and 15, the child does not have major birth defects. She does have mild sensorimotor delays. A review of non-Robertsonian jumping translocations is provided.

Gender identification of dried human bloodstains using fluorescence in situ hybridization.

Identification of the gender of an individual(s) from whom a bloodstain is derived represents important evidence in medicolegal cases. The efficacy of fluorescence in situ hybridization (FISH) using chromosome X and Y centromeric probes was tested to determine its ability to identify correctly the gender of extracted dried bloodstains. In this preliminary study, FISH correctly identified the gender of 2-week-old dried bloodstains in prepared mixtures of male-to-female blood as low as 1%. The technique is accurate, rapid, sensitive, easily performed and readily available. This application of FISH as a forensic laboratory technique holds great promise.

Identification of male epithelial cells in routine postcoital cervicovaginal smears using fluorescence in situ hybridization. Application in sexual assault and molestation.

In a prospective blinded controlled study, the efficacy of fluorescence in situ hybridization (FISH) to detect non-sperm male cells verifying sexual contact was examined. Cervicovaginal smears (CVS) from 40 women with reported post-coital intervals were examined for sperm by cytology and for sperm and non-sperm male cells by FISH using X and Y chromosome specific DNA probes. Fluorescence in situ hybridization identified sperm and/or non-sperm male cells in all specimens from women with positive coital histories, including when the partner had a vasectomy. Male cells were also detectable by FISH in CVS up to 3 weeks after coitus. In comparison, cytology identified sperm in 41% of the positive coital history cases, and none beyond 2 weeks. Fluorescence in situ hybridization is highly sensitive and specific in detecting male cells, and can be performed rapidly on routine CVS. Application of this technique can provide new and additional evidence of sexual contact when current tests are inconclusive.