HRAS and Cognitive impairment: For example, elevated levels of FPP and GGPP were observed in the brains of AD patients, and suppression of FTase or GGTase-I could mitigate Aβ-associated neuropathology in an AD mouse model.293 In another study, upregulated expression of FT and H-Ras farnesylation was observed in AD brains and the upregulation of FT and H-Ras farnesylation was associated with mild cognitive impairment, indicating that abnormal regulation of protein prenylation is involved in the AD pathogenic cascade.