β 3-Adrenergic receptors (β 3-ARs) are expressed predominantly in white and brown
adipose tissue, and β 3-selective agonists are potential anti-obesity drugs. However, the role
of β 3-ARs in normal physiology is unknown. To address this issue, homologous
recombination was used to generate mice that lack β 3-ARs. This was accomplished by
direct injection of a DNA-targeting construct into mouse zygotes. Twenty-three transgenic
mice were generated, of which two had targeted disruption of the β 3-AR gene. Mice that …