Influence of soil storage and exposure period on DNA recovery from teeth

A study was performed to determine the influence of garden soil on the deox yribonucleic acid (DNA) recovery from teeth depending on the duration of st orage, In the first series 24 teeth supplied by dentists were exposed to ga rden soil storage for a maximum of 18 weeks, Selected samples were excavate d for DNA extraction at time intervals of 6, 12 and 18 weeks. For the secon d series 20 teeth were stored for one year in garden soil. Following phenol /chloroform extraction with decalcification (first series) and without deca lcification prior to extraction (second series) DNA was quantified, amplifi ed using the polymerase chain reaction (PCR) for the tandem repeat loci DIS 80, tyrosine hydroxylase, intron 1 (TH01) and Von Willebrand factor, intron A (VWA) (first series), human alpha fibrinogen (FGA) (second series) and s equenced in the hypervariable regions 1 and 2 (HV1, HV2) of the mitochondri al DNA (second series). The DNA concentration of the extracts after the fir st 6 weeks in soil was reduced by more than 90%. Amplification and direct s equencing of HV1 and HV2 of the mitochondrial genome was the most successfu l DNA technique.