SNP: Single Nucleotide Polymorphism
Description There is an occasional isolated mutation that reveals a SNP between two or several DNA sequences. These variations involve a single base that is found randomly around every 100 to 300 bases on a genome. Most SNPs are found in the non-coding part of genomes and, in this case, the polymorphism has no functional implications. However, some of these occasional mutations affect the coding regions (cSNP) and the regulatory regions of genes. They can therefore modify the sequence of amino acids of the corresponding polypeptide or the mode of regulation of the gene expression. The cSNPs are particularly useful in mapping multi-factor diseases through a study of candidate genes involved in such diseases.