Detection of newborn aneuploidy by interphase fluorescence in situ hybridization.

Abstract

OBJECTIVE: To test fluorescence in situ hybridization (FISH) probes for rapid detection of aneuploidy of chromosomes 13, 18, 21, X, and Y from newborn uncultured blood samples. MATERIAL AND METHODS: Directly labeled, multicolored, commercially available FISH probes for the five aforementioned chromosomes were validated, and their hybridization efficiencies were established. In a blinded study, eight trisomic samples were tested by this FISH method. RESULTS: The hybridization efficiency based on metaphase evaluation of each of the five probes was 100%, and no cross-hybridization occurred. The mean interphase hybridization efficiencies of the probes for chromosomes 13, 18, 21, X, and Y were 97.4 %, 89.4 %, 96.1%, 94.4 %, and 100 %, respectively. The eight abnormal samples were identified as trisomy 21 (in six), trisomy 13 (in one), and trisomy 18 (in one). CONCLUSION: The screening of aneuploidy of newborns for chromosomes 13, 18, 21, X, or Y by interphase FISH is rapid, reliable, and cost-effective. The test is especially suitable for medically urgent cases as a screen, followed by a standard chromosome analysis.