Fig. 1.

Family trees; X chromosome alleles segregation. The position of ALAS2, AR and ZMYM3 genes are reported in the upper panel with respect to the X-Chromosome. In the family trees in red is indicated the mutated allele and in blue the wild-type allele of the X-chromosome. For each allele the size of AR and ZMYM3 polymorphisms are reported: the upper one is referred to AR and the lower one to ZMYM3. Symptomatic males are in black. Black dots indicate the presence of mutation in females; red circles indicate symptomatic females, dashed red circles indicate late onset of symptoms and dotted red circles indicates females showing only slight increase of PPIX in erythrocytes.