Haplotype database

Once the alignment has been made the combination of variations occurring at different places on the mtDNA strand can be identified and sequences can be compared with the reference sequence and crosscomparisons between different hair samples made. In Caucasians, there appear to be an average of around eight positions within the HVRs where the nucleotides differ between unrelated people and around 15 differences between people of African descent. As there is no recombination of the mtDNA the combination of variations in the HVRs is inherited as a single entity called a haplotype. The mitochondrial databases therefore count the frequency of the different haplotypes. 

Because of the variable phenotype in inclusion-body myopathy, PDB and FTD modifier genes were evaluated. From a database of 231 members of 15 families, 174 had an apohpoprotein E (APOE) genotype available for regression analysis. Analysis of the data suggested a potential link between the APOE 4 genotype and the FTD found in IBMPFD. hi contrast we observed no assodation between FTD and the MAPT H2 haplotype [33]. 

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