Direct chromosome preparations from chorionic villi: a method for obtaining extended chromosomes and recognizing mosaicism confined to the placenta.

ABSTRACT

A modified technique is described for obtaining extended metaphase chromosomes (600 bands) from direct preparations of chorionic villi, allowing rapid detection of subtle structural aberrations with minimal risk of maternal-cell contamination. Analysis of multiple individually processed villus fragments may be helpful in recognizing mosaicism confined to chorionic villi.