Distribution and origins of the MBL2 alleles in the world. Arrows denote the mutational steps between haplotypes (six between *1 and *4) and when dotted, the ancient migratory routes with their approximate ages . The haplotypes which could have been lost by natural selection and/or genetic drift were denoted by '?'. In bold: haplotypes generated before human out-of-Africa migration. Squared: more recent haplotypes, with geographically restricted distribution. KYA thousand years ago.