Mapping genetic alterations in tumors with single nucleotide polymorphisms.

Single nucleotide polymorphisms are the most abundant genetic markers in the human genome whose analyses can be easily conducted on a large scale. Most established methods for high-throughput single nucleotide polymorphism analyses are qualitative and are not suitable for genetic analysis of archived tumor specimens, which have compromised tissue integrity and normal tissue contaminations. Recent studies have focused on the development of quantitative methods for single nucleotide polymorphism analyses that can tolerate such imperfections in archived tissues. These methods have been used to measure the rate of allelic imbalance in small adenocarcinomas and to reveal novel correlations between allelic imbalance and disease progression in colorectal cancer. Therefore, quantitative single nucleotide polymorphism analysis provides a powerful tool for the identification of novel tumor markers and for the characterization of genetic alterations in human tumors.