Corresponds to heterozygous double mutation T400P and R516H in human CCT2, which is known to cause Leber congenital amaurosis (LCA), a hereditary congenital retinopathy; reduces the off-rate of ADP during ATP hydrolysis by CCT/TRiC; double mutation renders function of subunit CCT2, when it is outside the CCT/TRiC complex, to be defective in promoting autophagy