Frequency of RFA colour polymorphisms of human acrocentric chromosomes in caucasians: interrelationship with QFQ polymorphisms.

One hundred normal caucasians were studied by sequential QFQ and RFA in order to estimate the type and frequency of variation. Colour variants were classified into 1 of 6 colours by RFA and intensity variations into 1 of 5 levels by QFQ. The interrelationship between QFQ and RFA variants was also examined. It was found that there was no consistent relationship between negative or brilliant QFQ variants and the various colours observed with RFA. RFA colour polymorphisms for chromosomes 13, 14, 15, 21 and 22 were 33.0, 38.0, 28.0, 50.0 and 24.5% while QFQ frequencies were 56.5, 10.0, 10.0, 15.5 and 10.0% respectively. RFA is especially useful in studying the inheritance of chromosome 21.