For example, IGHV1-69, in addition to having many overlapping hotspots, has a highly hydrophobic CDR2 [51], a feature that facilitates its interaction with the gp41 and gp120 proteins of HIV and the E2 membrane fusion glycoprotein of HCV [52–54], and which may also explain its frequent usage in broadly-neutralizing antibodies (bnAbs) for influenza [51]. This evidence concerns the gene ITIH4 and influenza.