Figure 5. Chromatogram obtained on a Wave DHPLC system. Upperlane: PCR product of RAX exon 2 in a normal individual (family A:IV:2) showing one single peak, indicative of a unique product. Lowerlane: PCR product of the same region in an heterozygous individual (family A, father of IV:1). Three peaks corresponding to various heterodimers are visible. These heterodimers are obtained from different arrangements between wild-type and mutated DNA strands. y-axis: intensity, x-axis: retention time. The difference in the shape of the curves between normal and heterozygous individuals allows for an easy estimate of the frequency of the mutation in normal individuals.