Chromosome structure, study

Genotoxicity studies are required to identify compounds that can induce genetic damage ranging from single point gene mutations to gross alterations of chromosomal structure. Such effects are taken as indicative of the potential to cause cancer or heritable defects in humans. A standard battery of three types of test is recommended ... 

Simpson RT, Thoma F, Brubaker JM (1985) Chromatin reconstituted from tandemly repeated cloned DNA fragments and core histones a model system for study of higher order structure. Cell 42 799-808 Sugiyama S, Yoshino T, Kanahara H, Kobori T, Ohtani T (2003) Atomic force microscopic imaging of 30 nm chromatin fiber from partially relaxed plant chromosomes. Scanning 25 132-136 Sugiyama S, Yoshino T, Kanahara H, Shichiri M, Fukushi D, Ohtani T (2004) Effects of acetic acid treatment on plant chromosome structures analyzed by atomic force microscopy. Anal Biochem 324 39 4... 

These pioneering studies demonstrating nuclear differentiation and dedifferentiation are supported by a broad range of genetic and biochemical findings that indicate that chromosomal structural differences often can be correlated with changes in the potential for gene expression. 

Cytogenetic methods with plant root tips206—especially those of Vicia, Allium, and Hordeum—were widely used in the 1950s and 1960s to study the effects of chemicals on chromosomal structure and have played an important part in the development of cytogenetic tests in genetic toxicology. 

Holland, P. and Seabright, M., Effects of CS on lymphocyte chromosome structure, in Clinical and Preclinical Studies on Ortho Chlorobenzylidene Malononitrile (CS), Technical Note Number 82, Chemical Defence Establishment, Porton Down, Wiltshire, UK, 1971. 

All animals, plants, and fungi are eukaryotes. The number and size of the chromosomes of eukaryotes vary from one species to the next. For instance, humans have 23 pairs of chromosomes, while the Adder s Tongue fern has 631 pairs of chromosomes. But the chromosome structure is the same for all those organisms that have been studied. 

Doxorubicin is an antineoplastic/anthracycline antibiotic. It binds DNA and inhibits nucleic acid synthesis. Cell structure studies have demonstrated rapid cell penetration and perinuclear chromatin binding, rapid inhibition of mitotic activity and nucleic acid synthesis, and induction of mutagenesis and chromosomal aberrations. It is indicated in treatment of ovarian cancer in patients whose disease has progressed or recurred after platinum-based chemotherapy and in treatment of AIDS-related Kaposi s sarcoma in patients whose disease has progressed on prior combination chemotherapy or who are intolerant to such therapy. 

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