In 1996, Schonermark, Mester, Kempf, Blaser, Tscheche and Lenarz12 found that tissue invasion by cholesteatomas is related to the MMP2, which had also been described in 1996, by Gohlke, GomisRuth, Crabbe, Murphy, Docherty and Bode13, then called Gelatinase A, that bears a non-catalytic C terminal domain that bears a homologous sequence and haemopexin. Here, MMP2 is linked to cholesteatoma.