tokens: Using linkage disequilibrium analysis based on haplotype data of seven polymorphic markers close to the frataxin gene , the age of FRDA founding mutational event ( s ) is estimated to be at least 682 + / - 203 generations ( 95 % confidence interval 564 - 801 g ) , a dating which is consistent with little or no negative selection and provides further evidence for an ancient spread of a pre - mutation ( at - risk alleles ) in western Europe . .