To purify the neonatal diabetes variant SUR1/Kir6.2Q52R KATP channel, we co-expressed Kir6.2Q52R and SUR1 as independent polypeptides by transducing adherent mammalian COSm6 cells with recombinant adenovirus packaged with genes for rat Kir6.2Q52R and FLAG-tagged hamster SUR1 (see Methods). The gene discussed is ABCC8; the disease is diabetes mellitus.