Characterization of restriction enzyme banding polymorphisms in human chromosomes.

C and Re-banding chromosome heteromorphisms were analysed in blood cultures from 43 normal individuals. Restriction enzymes used were AluI, DdeI, HaeIII, and MboI. Chromosome pairs exhibiting heteromorphisms were: 1, 3, 4, 6, 9, 10, 12-16, and 18-22. Each individual showed a specific combination of C- and Re-banding heteromorphisms not shared by any other individual in the series. Some polymorphisms could be detected by all the banding methods used. Others could be detected by some of the banding methods, and in some cases by only one of the banding methods used. The efficiency of each banding method to detect chromosomal polymorphisms depended on the type of polymorphism and the chromosomal pair analysed. Our results indicate that Re-banding polymorphisms occur due to changes in base composition of different fractions of heterochromatin or due to the presence or absence of different heterochromatic subsets. C- and Re-banding are complementary methods that expand the identification of chromosomal markers and which can be used to identify the parental origin of individual chromosomes.