GREM1 and occult macular dystrophy: The gene expression of the PI3K-Akt signaling pathway and focal adhesion was prominently upregulated in HCLS, suggesting that the degradation of μHAp and chelating of calcium ions by catecholamine moieties might promote osteogenesis (OMD, OGN, GREM1, and COL14A1 genes in Fig. 6e3).