Microsatellite analysis

The MSI is used as a diagnostic criterion of replication errors caused by various mutations in at least five mismatch repair genes (Lynch and Smyrk, 1996). Therefore, MSI analysis is useful in clinical practice to identify patients with hereditary nonpolyposis colorectal cancer. Raedle et al. (1999) have presented a rapid DNA extraction method (rapid microsatellite analysis) for analyzing replication errors in paraffin-embedded tissues. 

Raedle, J., Brieger, A., Trojan, J., Hardt, T., Herrmann, G., and Zeuzem, S. 1999. Evaluation of rapid microsatellite analysis of paraffin embedded specimens in screening for hereditary nonpolyposis colorectal cancer. Mod. Pathol. 72 485-491. 

Microsatellites are hypervariable co-dominant loci composed of arrays of 2-9 bp repeating motifs. Differences in the number of repeat motifs in an array define microsatellite polymorphisms. Method development requires the identification of microsatellite loci, and for each locus, the design of PCR primers to anneal to conserved regions flanking the microsatellite. Analysis involves PCR amplification with fluorescently labeled primers followed by electrophoresis to distinguish microsatellite alleles of different array size. 

Esposito DL, Palmirotta R, Veri MC, Mammarella S, D Amico F, Curia MC et al (1998) Optimized PCR labeling in mutational and microsatellite analysis. Clin Chem 44 1381-1387... 

Pig cloning will thus have a marked impact on tire optimization of meat production and xenohansplantation. To clone pigs from differentiated cells, tire nuclei of porcine Sus scrofa) fetal fibroblasts were injected into enucleated oocytes, and the development was induced by electro activation. The transfer of 110 cloned embryos to foiu sunogate mothers produced an apparently normal female piglet. The clonal provenance of the piglet was indicated by her coat color and confirmed by DNA microsatellite analysis. 

TABLE 1.7 Commercially Available Kits for Microsatellite Analysis... 

By microsatellite analysis DNA fingerprints can be made from almost all mammals. Primers are published for a wide variety of mammals, birds, and fishes. For some animal species used in agriculmre, commercial PCR kits are available (Table 1.7) for other species, sets of markers are available some of which were tested in ring trials (sheep, goat, pig). In contrast to the analysis of human DNA, currentiy no aUelic ladders are commercially available for these marker sets except for porcine microsatellite analysis with a kit from Biotype. 

Example 3 A fish retailer declared smoked salmon to be wild from salmon captured in a specific river. The food analyst has doubts about this declaration he thinks that the meat is from farmed salmon. In this case reference samples must be collected from salmon captured in the river and from salmon raised on aU farms. After microsatellite analysis, allele frequencies have to be determined and the likelihood has to be calculated whether the salmon can be from the river population or from one of the farm populations. 

G6mez, A., Adcock, G.I., Lunt, D.H., Carvalho, G.R. (2002b). The interplay between colonisation history and gene flow in passively dispersing zooplankton microsatellite analysis of rotifer resting egg banks. Journal of Evolutionary Biology 15,158-171. 

Can be performed in some CPS deficiency (microsatellite analysis) most OTC deficiencies (RFLP rarely mutation analysis as first step), AS, AL, argi-nase deficiency, LPI, HHH and HIHA syndrome, not in NAGS deficiency. 

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). 

Microsatellites-the repeated units are typically 2-4 bp, and the length of the entire repeat is generally less than 150 bp. This dass often referred to as STRs (simple tandem repeats) is most typically amplified by a PCR for paternity testing, forensic cases, or gene linkage analysis (see Section II, Chapter 4 Polymorphic Markers and Linkage Analysis). 

Hale, A. L. (2003). Screening potato genotypes for antioxidant activity, identification of the responsible compounds, and differentiating Russet Norkotah strains using AFLR and microsatellite marker analysis, Vol. Rh.D. Texas A M University, http //handle.tamu.edU/1969.l/1602, Rh.D. Thesis, College Station. 

Another example is the study of microsatellites that are short DNA loci having simple sequence repeats that are widely distributed throughout the human genome. They are a valuable source for human genetic linkage analysis and molecular cancer research... 

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