Haplotype networks in IRS1 and IRS2. The size of ovals and squares is proportional to the number of individuals that share a haplotype. The haplotypes with the highest outgroup probability are displayed as a square, the other haplotypes are displayed as ovals . Each node represents a mutation step between haplotypes. The numbers of mutation steps between the networks of the IRS2 and the network of the IRS1 are provided (see arrows). The haplotypes of IRS1 belong to four different clusters, separated by at least ten mutation steps.