Single Nucleotide Polymorphism and its Application in Mapping Loci Involved in Developing Human Diseases and Traits

Common diseases or traits in humans are often influenced by complex interactions among multiple genes as well as environmental and lifestyle factors rather than being attributable to a genetic variation within a single gene. Identification of genes that confer disease susceptibility can be facilitated by studying DNA markers such as single nucleotide polymorphism (SNP) associated with a disease trait. Genome-wide association approaches offers a systematic analysis of the association of hundreds of thousands of SNPs with a quantitative complex trait. This method has been successfully applied to a wide variety of common human diseases and traits, and has generated valuable findings that have improved the understanding of the genetic basis of many complex traits. This article outlines the general mapping process and methods, highlights the success stories, and describes some limitations and challenges that lie ahead. Single Nucleotide Polymorphism and its Application in Mapping Loci Involved in Developing Human Diseases and Traits