QKO cells expressing EGFP-GRAM-H were transfected with either mRuby control, mRuby-GRAMD1b, mRuby-tagged mutant GRAMD1b in which the StART-like domain cannot transport cholesterol [mRuby-GRAMD1b (5P)], or mRuby-GRAMD1b (5P) additionally carrying an intellectual disability-associated mutation within the GRAM domain, which impairs its ability to sense accessible cholesterol [mRuby-GRAMD1b (R189W & 5P)]45,53,88. This evidence concerns the gene GRAMD1B and Intellectual disability.