VALIDATION OF MITOCHONDRIAL-DNA SEQUENCING FOR FORENSIC CASEWORK ANALYSIS

Two sets of studies were performed to evaluate the forensic utility of sequencing human mitochondrial DNA (mtDNA) derived from various tissu es and amplified by the polymerase chain reaction (PCR). Sequencing wa s performed on a Perkin-Elmer/Applied Biosystems Division (PE/ABD) aut omated DNA sequencer (model 373A). The first set of experiments includ ed typical validation studies that had previously been conducted on fo rensic DNA markers, such as: chemical contaminant effects on DNA from blood and semen and the effect of typing DNA extracted from body fluid samples deposited on various substrates. A second set of experiments was performed strictly on human hair shafts. These studies included ty ping mtDNA from hairs that were: (1) from different body areas, (2) ch emically treated, (3) from deceased individuals, and (4) deliberately contaminated with various body fluids. The data confirm that PCR-based mtDNA typing by direct automated sequencing is a valid and reliable m eans of forensic identification.