Mitochondrial DNA point mutations detected in four cases of sudden infant death syndrome

The aim of this study was to investigate the tRNA(Leu(UUR)) gene and the fi rst part of the ND1 gene in mitochondrial DNA (mtDNA) in cases of sudden in fant death syndrome (SIDS). A total of 158 cases of SIDS and 97 controls we re included in the study, and the base pairs in the range 3230-3330 were in vestigated using polymerase chain reaction (PCR) and temporal temperature g radient electrophoresis (TTGE). If a band shift was detected by TTGE, the a rea investigated and the D-loop was sequenced. Three different point mutati ons (T3290C, T3308C and T3308G) were detected in four of the SIDS cases, wh ile none of the controls were mutated. We also found a high D-loop substitu tion rate in these four cases. The findings indicate that mtDNA mutations m ay play a role in some cases of SIDS.