Fig. 3.

Phylogenetic tree of mammalian VH genes including the platypus VHδ and monotreme Vµ. The three major VH clans are bracketed. The platypus VHδ is boxed and the clade containing platypus VHδ along with platypus and echidna Vµ is in bold and indicated by a smaller bracket in VH clan III. The three-digit numbers following the VH gene labels are the last three digits of the GenBank accession number referenced in supplementary table S2, Supplementary Material online. The numbers following the platypus and echidna Vµ labels are clone numbers. The tree presented was generated using the Minimum Evolution method. Similar topology was generation using the Neighbor Joining method.