Microsatellite

Growth inhibition by TGF- 3, associated with inhibition of c-myc, cdks, reduction in cyclin D1 levels, and inhibition of cdk-4-associated Rb kinase activity, as well as induction of cdk inhibitors pi5 and p27, has been noted in intestinal epithelial cells. Loss of responsiveness to growth inhibition from TGF- 3 occurs in many cell types including breast, colorectal carcinoma, and pancreatic carcinoma cells. Mutational inactivation of T 3RH represents one mechanism of this process, which in many cases, leads to the development of gastrointestinal cancer. Thirteen percent of colorectal carcinomas are thought to be associated with a replication error (RER) or microsatellite instability phenotype. Subsequent inactivation of T 3RII and... 

Microsatellite repeat sequences Dispersed or group repeat sequences of 2-5 bp repeated up to 50 times. May occur at 50-100 thousand locations in the genome. 

S. Longato and P. Bonfante, Molecular identification of mycorrhizal fungi by direct amplification of microsatellite regions. Mycol. Re. i. 101 425 (1997). 

F. Martin, G. Costa, C. Delaruelle, and J. Diez, Genomic fingerprinting of ectomy-corrhizal fungi by microsatellite-primed PCR, Mycorrhiza Mcimial (A Varma, B Hock, eds,). Springer lab manual, 1998, pp, 463-474. 

Genetic Familial prostate cancer is inherited in an autosomal dominant manner. Mutations in p53, Rb, E-cahedrin, a-catenin, androgen receptor, KAII, microsatellite instability, loss of heterozygocity at 1, 2q, 12p, 15q, 16p, and 16q. Candidate prostate cancer gene locus identified on chromosome 1. 

Analysis of mini- and microsatellites, and other repetitive elements... 

Conole, J.C., Chilton, N.B., Jarvis, T. and Gasser, R.B. (2001) Mutation scanning analysis of microsatellite variability in the ITS-2 (precursor rRNA) for three species of Metastrongylus (Nematoda Metastrongyloidea). Parasitology (in press). 

Fisher, M.C. and Viney, M.E. (1996) Microsatellites of the parasitic nematode Strongybides ratti. Molecular and Biochemical Parasitobgy 80, 221-224. 

Goldstein, D.B. and Clark, A.G. (1995) Microsatellite variation in North American populations of Drosophila melanogaster. Nucleic Acids Research 23, 3882-3886. 

Hoekstra, R., Criado-Fomelio, A., Fakkeldij, J., Bergman, J. and Roos, M.H. (1997) Microsatellites of the parasitic nematode Haemonchus contortus polymorphism and linkage with a direct repeat. Molecular and Biochemical Parasitology 89, 97-107. 

Love, J.M., Knight, A.M., McAleer, M.A. and Todd, J.A. (1990) Towards construction of a high resolution map of the mouse genome using PCR-analysed microsatellites. Nucleic Acids Research 18, 4123 1130. 

Zarlenga, D.S., Aschenbrenner, R.A. and Lichtenfels, J.R. (1996) Variations in microsatellite sequences provide evidence for population differences and multiple ribosomal gene repeats within Trichinella pseudospiralis. Journal of Parasitology 82, 534-538. 

Cui H, Horon IL, Ohlsson R, Hamilton SR, Feinberg AP. Loss of imprinting in normal tissue of colorectal cancer patients with microsatellite instability. Nature Med 1998 4[11] 1276 1280. 

Although less common than SNPs, another type of genetic polymorphism is the variable nucleotide tandem repeat (VNTR), also called microsatellite [65]. 

Microsatellite markers have been extensively used in family studies. These are regions of variation, mostly (CA) repeats, which are distributed throughout the genome. There are potentially as many as 105 loci, each of which has many alleles and these markers are, therefore, highly informative. Microsatellites can be typed by automated multiplex PCR. 

Marker Known location on a chromosome (e.g., restriction enzyme cutting site, gene) whose inheritance can be monitored. Markers are located in or close to coding regions of DNA (i.e., genes) or in segments of DNA with no known coding function but whose pattern of inheritance can be determined (i.e., microsatellites). 

Polymorphism A common (i.e., at least 1% prevalence of the minor allele in the population) sequence variation observed in an individual at a polymorphic site. Polymorphisms include nucleotide substitutions, insertions, deletions and microsatellites. They may be functional or silent, i.e., they do not result in detectable differences in gene expression or protein function. 

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