Two-dimensional gene scanning: Exploring human genetic variability

Current methods for mutation detection are not optimized for the generation of highly accurate data on multiple genes of hundreds of individuals in po pulation-based studies. Two-dimensional gene scanning (TDGS) is a high-reso lution system for detecting mutational variants in multiple genes in parall el. TDGS is based on a combination of extensive multiplex polymerase chain reaction (PCR) and two-dimensional (2-D) DNA electrophoresis. The latter in volves a size separation step followed by denaturing gradient gel electroph oresis (DGGE). TDGS tests for a number of large human disease genes have be en designed, using a computer program to optimally position PCR primers aro und the relevant target sequences (e.g., exons) and evaluated using panels of samples with previously detected mutations. The results indicate a high sensitivity and specificity, equal to nucleotide sequencing, which is gener ally considered as the gold standard. Here, we describe the different compo nents of the TDGS process and its potential application as a high-throughpu t system for the systematic identification of human gene variants.