Gawron K, et al. - Researchers gauged the processes associated with the excessive production of collagen I in hereditary gingival fibromatosis (HGF). Findings suggested an association of fibrosis in HGF gingival tissues with increased synthesis of heat shock protein 47 (HSP47). An in vitro study confirmed this finding, where excessive production of collagen I was related to increased synthesis of HSP47, TGF-β1 and connective tissue growth factor (CTGF) by HGF gingival fibroblasts. Furthermore, increased synthesis of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) was identified as one of the processes associated with collagen I overproduction in HGF fibroblasts by the shift in the TIMP-1/matrix metalloproteinase-1 (MMP-1) ratio.