MHMEJ was found in joins of V-D and D-J elements of TRB sequences (a). The diagram shows the frequency of specific joins mediated by MH, expressed as percentage of all unique sequences. Corresponding sequences found in the joint region are shown below. Some joins of TRBV5.1, TRBV5.4, TRBV5.6 with TRBD1 had 1nt deletion.
In contrast, MHMEJ was found only in three joins of the IGH locus, and almost exclusively in P2 (b). Some sequences had a 1nt insertion (indicated in blue) in the corresponding J segment.