Ultrarapid detection of sex chromosomes with the use of fluorescence in situ hybridization with direct label DNA probes in single human blastomeres, spermatozoa, amniocytes, and lymphocytes

Objective: To assess the ultrarapid fluorescence in situ hybridization (FISH) procedure with a 1-minute hybridization time for gender determination. Design: Fluorescence in situ hybridization with direct label fluorescence DNA probes for chromosomes X and Y were tested with the use of different hybridization times and different cell types. Setting: Hospital-based IVF program. Intervention(s): The efficiency of the FISH procedure with different hybridization times was compared with the use of male lymphocytes. The same FISH procedure, but with only 1-minute hybridization, was carried out in human blastomeres, spermatozoa, uncultured amniocytes, male lymphocytes, and female lymphocytes. Main Outcome Measure(s): Percentages of nuclei with positive signals. Result(s): The percentages of nuclei with positive signals in lymphocytes with hybridization times of 1, 3, 4, 10, 30, and 45 minutes were 97%, 97%, 98%, 98%, 98%, and 98%, respectively. The percentages of nuclei with positive signals after FISH with a 1-minute hybridization time in single blastomeres, spermatozoa, amniocytes, male lymphocytes, and female lymphocytes were 94%, 96%, 96%, 98%, and 97%, respectively. Conclusion(s): Chromosomes X and Y of human blastomeres, spermatozoa, uncultured amniocytes, and lymphocytes can be detected rapidly with the use of this ultrarapid FISH procedure with a 1-minute hybridization time.