Why Do Mice Have ADAMTS5?

Human osteoarthritis is a progressive disease of the joints characterized by degradation of the cartilage, a major component of which is aggrecan. Several groups of researchers have recently identified ADAMST5 as the primary enzyme responsible for the degradation of aggrecan and the resulting loss of cartilage in mice.

Adult mice lacking the active portion of the ADAMST5 gene (knockout mice) were found to have no gross abnormalities and 17 tissue types as well as blood and serum were examined and found to be normal. Knockout mice underwent surgery to simulate joint injury. A significant reduction in cartilage destruction was observed in these mice compared to wild-type mice.

Again (see the previous article), ADAMST5 appears to confer no benefit and actually exacerbate injury and yet has been conserved in the mouse genome.

Ref: Nature 31-Mar-2005 Pg 644