In contrast, Santiago and colleagues suggested that a lack of exon 2 in the mA3 made in BALB/c (or A.BY) susceptible mice contributes to the inability of mA3 from these backgrounds to inhibit infection, although this transcript was not detected in the studies by Takeda et al. and our lab has more recently found that the major transcript in BALB/c mice contains exon 2 [66]. The gene discussed is PNMA3; the disease is infection.