ADAMTS5, the main aggrecanase, is a protein that appears to play a functional role in development of white adipose tissue (WAT) and brown adipose tissue (BAT) and in browning of WAT. ADAMTS5 deficient or knockout (ADAMTS5-/- or KO) mice indeed showed lower WAT mass, higher mass of interscapular BAT and enhanced browning of WAT, as indicated by elevated uncoupling-protein-1 (UCP-1) levels. In addition, ADAMTS5-/- mice appeared to be protected from non-alcoholic steatohepatitis (NASH) when kept on a Western type diet. These observations were made with the ADAMTS5-/--P mice originally generated by Pfizer, in collaboration with Lexicon Genetics. To provide confirmation of these observations, we have obtained a second strain of ADAMTS5 deficient mice, generated independently by Deltagen Inc.