Rapid prenatal diagnosis by fluorescent in situ hybridization of chorionic villi: an adjunct to long-term culture and karyotype.

OBJECTIVE

This series was designed to assess in a pilot study the feasibility of using fluorescence in situ hybridization on chorionic villi.

STUDY DESIGN

We constructed probes derived from specific subregions of human chromosomes 21, 18, 13, X, and Y that give a single copylike signal when used in conjunction with suppression hybridization.

RESULTS

In a blind series of 47 samples all, including one trisomy 21, were correctly identified. The samples were correctly classified as disomic for five chromosomes.

CONCLUSIONS

The combination of chromosome-specific probe sets composed primarily of cosmid contigs and optimized hybridization and detection allowed accurate chromosome enumeration in uncultured human chorionic villi; these results are consistent with those obtained by traditional cytogenetic analysis and suggest a use for fluorescence in situ hybridization as an adjunct to karyotyping when rapid results are needed.