Dendrogram of the 86 MDR families. A ClustalW neighbour-joining dendrogram of representative sequences from the 86 MDR families. Blue lines indicate families with at least one human member and green lines indicate families with at least one eukaryotic member. The families with members that bind NAD and two Zn2+ are generally found in the upper half of the dendrogram (indicated with a yellow frame) while those with members that bind NADP and no Zn2+ are almost exclusively found in the lower half (indicated with a purple frame). Exceptions to the NAD/NADP cofactor preference indicated within the frames are highlighted by labels in the opposing colour. Exceptions to the number of bound Zn2+ indicated within the frames are shown using bullet symbols. Two filled bullets correspond to 2 Zn2+, one filled bullet to 1 Zn2+, and an unfilled bullet to 0 Zn2+. Half-bullet symbols are used to indicate cases where the ligands for one of the Zn2+ are conserved only among part of the family members. Although bootstrap values are consistently low (not shown), six branch points were observed in over 900 of the 1000 bootstrap reconstructions of the dendrogram (indicated using red diamonds).