Polymorphism of Human Constitutive Heterochromatin

Abstract

Genetic polymorphism has been demonstrated in man for many characteristics including blood groups, serum proteins, tissue enzymes, and hemoglobins. A class of chromosomal polymorphism involving constitutive heterochromatin has now been found. Through the use of a special technique that permits visualization of heterochromatin, seven heterochromatin variants have been found among four individuals. These results suggest a very high frequency of variability of heterochromatin in the population.

Cytotaxonomic Investigation of the GenusNigella(Helleboreae) with C-Banding Techniques

“…A terminal CJ-band is visible but only in one chromosome of the pair (a"'). Polymorphism of the C-bands has been reported in man by CRAIG-HOLMES and SHAW (1971) and CRAIG-HOLMES et al (1973), by FoREJT (1973) in mouse and by YosmA and SAGAI (1975) in various rat species.…”

Gene mapping and leader polypeptide sequence of human glucocerebrosidase: implications for Gaucher disease.

“…In addition, the proximal location of the gene to the highly heteromorphic lqh region should allow observation of segregation of mutant alleles by linkage to these heteromorphisms. By using C-, Giemsa-11, and lateral asymmetry banding, it is estimated that the segregation patterns of most chromosomes 1 (27,28) can be unambiguously followed. If the chromosome 1 heteromorphic region and the structural gene for glucocerebrosidase are closely linked, it should be possible to use this technique to reliably identify both homozygotes and heterozygotes for Gaucher disease.…”

Islands of euchromatin-like sequence and expressed polymorphic sequences within the short arm of human chromosome 21

“…Cytogenetic data show that the p arms contain large heterochromatic regions (Craig-Holmes and Shaw 1971;Verma et al 1977). Molecular evidence suggests that they are composed mainly of satellite and other repeat families, including satellites I (Kalitsis et al 1993), II (Hollis and Hindley 1988), III (Choo et al 1990), ␤ (Waye and Willard 1989), and repeats ChAB4 (Cserpán et al 2002), 724 (Kurnit et al 1986), and D4Z4-like (Lyle et al 1995).…”