Mitochondrial DNA sequences for 118 individuals from northeastern Spain

A population database was generated from 118 unrelated Caucasoid individual s living in Spain. Sequence polymorphisms of the mitochondrial DNA (mtDNA) control region, hypervariable regions I and II (HVRI and HVRII) were determ ined using the polymerase chain reaction (PCR) and direct sequencing. A tot al of 102 different sequences were found as defined by 105 variable positio ns. The most common sequence occurred six times, and this sequence is also the most frequent in other European populations such as Austria, Germany an d Britain. The mean pair-wise difference for the two HVR regions taken toge ther was 7.74. The study revealed that transitions made up the majority of the variations (88%), whereas we observed a significantly lower frequency o f transversions (8%). Also one individual in this study was observed with t wo positions of heteroplasmy at nucleotides 150 (C/T) and 153 (G/A). A stat istical estimate of the results for this population showed a genetic divers ity of 0.99. The probability of two random individuals showing identical mt DNA haplotypes is 1.3%. In order to use the mtDNA analysis in forensic case work, we consider that it is of crucial importance to know the frequency of the different sequences of mtDNA, and this data base study could be a usef ul tool to statistically evaluate the results.