CHRNB4 and lung cancer: Compared to normal lung, both tumors share: i) transcriptional dysregulation of CHRNA3/CHRNA5/CHRNB4 (α3, α5, β4 subunits) at the chromosomal locus that predisposes to lung cancer; and ii) decreased expression of CHRFAM7A (dupα7 subunit); this last subunit negatively modulates α7-nAChR activity in oocytes.