Mutation and Polymorphism Detection: A Technical Overview

Analysis of DNA variation (polymorphism and mutations) is one of the most common challenges faced by molecular biologists. Studies of polymorphisms and mutations as molecular markers of or underlying causes of disease have confirmed the importance of mutation and polymorphism detection. With mutation detection currently being so important for the study of genetic diseases, gene discovery, and solving problems of basic biology, there is a large demand for quick and relatively cheap methods for mutation detection. Therefore, many different methods have been developed for detecting new mutations and screening populations for known mutations or polymorphisms. Traditional mutation detection systems, such as restriction fragment length polymorphism and denaturing gradient gel electrophoresis, have their limitations. With restriction fragment length polymorphism, the mutational event needs to either create or destroy a restriction site (1 ). With denaturing gradient gel electrophoresis, although a change at a restriction digest site is not required, this method may only detect about 50% of possible mutations and polymorphisms (1 ). The use of polymerase chain reaction (PCR)-based mutation and polymorphism detection systems increase the sensitivity and accuracy of the screening methods. This chapter will introduce some of the available detection methods and discuss the problems associated with these techniques.