Supporting the hypothesis that ALDH1a1 drives rexinoid activation while ALDH1a2/1a3 drives retinoid activation, ALDH1a1 knockout mice exhibit increased brown fat synthesis and obesity resistance (Kiefer et al., 2012), which phenocopies RXRγ but not RAR knockout (Haugen et al., 2004). The gene discussed is ALDH1A1; the disease is obesity disorder.