C-band heterochromatin polymorphism of human chromosomes 1, 9, 16, Y.

: Results are presented of a C-band investigation of the chromosomes 1, 9, 16, Y of two unselected populations from Central Italy and of 30 normal families. A high incidence of polymorphism was observed in these populations. Moreover, though the majority of the observed variants were inherited from parents to child in a Mendelian way, 3/30 children presented differences from the parental pattern. The results are discussed together with the data of other reports.