An unstable giant satellite associated with chromosomes 21 and 22 in the same individual

• Published in: American journal of human genetics 1985-05, Vol.37 (3), p.553-560
• Main Authors: LIVINGSTON, G. K, LOCKEY, J. E, WITT, K. S, ROGERS, S. W
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Chemical mutagenesis; Chromosomes, Human, 21-22 and Y - ultrastructure; Female; Fibroblasts - ultrastructure; Humans; Insecticides - adverse effects; Karyotyping; Lymphocytes - ultrastructure; Medical sciences; Occupational Diseases - chemically induced; Occupational Diseases - genetics; Polymorphism, Genetic; Sister Chromatid Exchange - drug effects; Staining and Labeling; Time Factors; Toxicology
• ISSN: 0002-9297; 1537-6605

The short arms of the acrocentric chromosomes are among the most common sites in which to find human chromosomal heteromorphisms. Heteromorphic chromosomes are noted for their variability between individuals and populations; however, they generally are consistent within an individual. Contrary to this general rule, a normal female was found to have a giant satellite on the short arm of a chromosome 22 in most lymphocytes and fibroblasts, but in other cells, it was attached to a chromosome 21. Furthermore, in some cells, it was found on multiple chromosomes, that is, on both 22's or on a 21 and a 22. The familial nature of this heteromorphism was established when it was found in the woman's mother, where it was confined exclusively to chromosome 22. These results suggest an unstable giant satellite associated with both G-group chromosomes of a normal individual. Results are discussed in the light of the patient's occupational exposure to insecticides at a mushroom farm.