Polymorphic variants in human chromosome 15.

We found eight polymorphic variants in human chromosome 15 using Q, C, Q-C and Ag-NOR staining methods. These variants included brightly or dully fluorescent pericentric segments and satellites, giant satellites, increased amounts of short arm hetrochromatin (ph+) and darkly (C band-positive) or lightly (C band-negative) Giemsa-stained pericentric Q-negative segments. These staining properties indicated that the entire short arm of 15 contained at least four distinct chromatin segments: Q-negative centromeric heterochromatin, a Q-variable distal segment, a Q-negative satellite stalk, and Q-variable satellites, in that order, from proximal to distal ends. The BrdU-Hoechst 33258-stained R bands (RBH) and high resolution G subbands were also studied for karyologic characterization of chromosome 15. Most of these variants were reported also in 13, but insufficiently documented in other D and G chromosomes. Together with polymorpic pericentric fluorochromes seen in 3 and 4, Yq, and nonpathogenic t(D;Yq), the pattern of these variants can be used as karyologic fingerprints for identification of each individual and his or her cell explants both in vivo and in vitro.