DNA chip arrays hold considerable promise for diagnostic sequencing of polymerase chain reaction (PCR) products. To date, however, arrays have been relatively expensive, complex to use and difficult to interpret, preventing their adaptation to the clinical lab. A moderate density array method has been developed that enables efficient, easy-to-interpret and robust solid-phase PCR product sequencing. Here, the results ofMycobacterium tuberculosisrifampin resistance mutation detection by primer-extension-based sequence scanning of therpoB gene ofM. tuberculosisare presented. Rifampin resistant clinical isolates were identified in as little as 1 h post PCR amplification with visual results detection.