Centromeric banding (C) of sequentially Q- and R-banded human chromosomes.

A modified C-banding technique is described that produces C bands on human chromosomes after sequential Q and R banding and retains good chromosome morphology. Despite the considerable exposure to UV light during sequential Q and R bandings, clear C bands could still be achieved. Employing the present technique, Q, R, and C polymorphisms can be recorded on a single metaphase.