NeighborNet tree of M. m. musculus haplotypes based on the mitochondrial DNA control region. Pol, Chn, Ukr, Slo, Ger, Geo, Tur, and Cze are used as abbreviations for Portugal, China, Ukraine, Slovenia, Germany, Georgia, Turkey, and Czech Republic, respectively. Haplotypes from the above regions are shaded. The remaining, unmarked haplotypes were all from China.