page 435 | | page 436 |
The genome is composed of DNA, an antiparallel, double-stranded helical polymer of deoxyribonucleotides,
stabilized by hydrogen binding between complementary bases. The DNA is packaged in the chromosome in a highly organized, condensed structure. Genetic information is replicated by a semi-conservative mechanism in which the parental strands are separated and both act as templates for daughter DNA. The replication of DNA is a complex, stringently regulated process. DNA is the only polymer in the body that is repaired, rather than degraded, following chemical or biological modification. Repair mechanisms generally involve excision of modified bases and replacement, using the unmodified strand as a template.
|
- What are the possible functions of unusual forms of DNA?
- Discuss the possible roles for middle repetitive and highly repetitive sequences in DNA.
- Fragile X syndrome is the most common form of inherited mental retardation in humans. What is the role of non-genomic DNA in the pathogenesis of this disease?
- Hereditary nonpolyposis colon cancer results from a defect in DNA mismatch repair. Why is this condition autosomal dominant?
|
Ahmed A, Tollefsbol T. Telomeres and telomerase: basic science implications for aging. J Am Geriatr Soc 2001;49:1105-1109.
Full article
|
Cleaver JE, Crowley E. UV damage, DNA repair and skin carcinogenesis. Front Biosci 2002;7:d1024-d1043.
|
Norgauer J, Idzko M, Panther E, Hellstern O, Herouy Y. Xeroderma Pigmentosum. Eur J Dermatol 2003;13:4-9.
|
Sekiguchi M, Tsuzuki T. Oxidative nucleotide damage: consequences and prevention. Oncogene 2002;21:8895-8904.
Full article
|
Venter JC, et al. (2001) The sequence of the human genome. Science 2001;291:1304-1351.
Full article
|
Watson JD. A passion for DNA. Genes, genomes and society. (Oxford University Press: Oxford, 2000) 250pp.
Full article
|
Watson JD. The double helix: a personal account of the discovery of the structure of DNA. (Norton: New York, 1980) 298pp.
Full article
|
Wilson III D, Sofinowski T, McNeill D. Repair mechanisms for oxidative DNA damage. Front Biosci 2003;8:963-981.
|
Zannis-Hadjopoulos M, Price GB. Eukaryotic DNA replication. J Cell Biochem Suppl 1999;32/33:1-14.
Full article
|
Graphics: www.accessexcellence.org/AB/GG/structure.html
Full article
|
Human Genome Project: www.ornl.gov/TechResources/Human_Genome/
Full article
|
General educational: www.dnaftb.org; www.dnalc.org; www.dnai.org; www.accessexcellence.org/AB/GG/
Full article
|
|