Figure 1

hs1.2 location and known human variants. a) The locus of the Ig heavy chain with the variable, constant and regulatory elements. The three enhancers of 3’RR1 and 3’RR2 are conserved in order: hs3 (orange), hs1.2 (rainbow), hs4 (dark green). Nevertheless, hs1.2 sequence is inverted in 3’RR2 with respect to the 3’RR1. b) Regulatory regions at the 3’ of the constant alpha1 and alpha2 genes (blue). A 20 bp conserved repeats is shown in violet, while the palindromic regions in light blue. c) Scheme of the six variants of the enhancer hs1.2 known in human (see included caption box for colors explanation).