ACCESSING GENETIC INFORMATION WITH HIGH-DENSITY DNA ARRAYS

Rapid access to genetic information is central to the revolution takin g place in molecular genetics. The simultaneous analysis of the entire human mitochondrial genome is described here, DNA arrays containing u p to 135,000 probes complementary to the 16.6-kilobase human mitochond rial genome were generated by light-directed chemical synthesis, A two -color labeling scheme was developed that allows simultaneous comparis on of a polymorphic target to a reference DNA or RNA. Complete hybridi zation patterns were revealed in a matter of minutes. Sequence polymor phisms were detected with single-base resolution and unprecedented eff iciency, The methods described are generic and can be used to address a variety of questions in molecular genetics including gene expression , genetic linkage, and genetic variability.