Therefore, any therapeutic intervention to increase DUSP9 expression or to control the activity of ERK1/2, JNK, p38 MAPK and/or ASK1 kinases could be beneficial for patients presenting metabolic syndromes such as type 2 diabetes, morbid obesity, liver cirrhosis, NAFLD or its most severe form, NASH. This evidence concerns the gene MAP3K5 and type 2 diabetes mellitus.