Genotyping of Single Nucleotide Polymorphisms

Abstract

Single nucleotide polymorphisms (SNPs) are the most abundant DNA variations in human genome. Numerous reports have indicated that SNPs are closely associated with diseases such as cardiovascular diseases, different types of cancer, and other genetic diseases. As such, SNPs are currently considered as potentially important cancer biomarkers that may significantly improve cancer diagnosis and prognosis, aid drug development, and offer personalized treatments for cancer patients. The importance of SNPs, especially on the genetic diseases, has urged researchers to develop SNP detection methods for their sensitive and accurate identification in the presence of excessive wild-type (WT) genes. Unlike other DNA assays, the intrinsically subtle difference between WT and mutant genes—a single-base variation—makes it a challenging task to specifically detect low abundant SNPs out of large amounts of coexisting WT genes. To date, many methods have been proposed for SNP detection, and they can be classified into two categories—allele-specific hybridization methods and allele-specific enzymatic methods. A thorough review of the state-of-the-art detection technologies for SNPs will be helpful to researchers in the development of more efficient SNP genotyping technologies. In this article, recent advances in the detection and genotyping of SNPs are summarized, and emerging techniques for SNP genotyping are assessed.