GNAS and Cognitive impairment: The 5 overlapping DMGs identified under CCH are Striated muscle Preferentially Expressed protein kinase (SPEG), Acting Gamma 1 (ACTG1), Dead-Box Helicase 3 Y-linked (DDX3Y), Guanine Nucleotide binding protein, Alpha Stimulating (GNAS) and Paired box 6 (PAX6) where the first is associated with mild cognitive impairment and the latter are all associated with AD.