Uwai et al. reported an intron 16 polymorphism (Ex-76 T/A) that resulted in downregulation of P-gp function in renal carcinoma cells.[13] The Ex-76 T/A has been shown to be in linkage disequilibrium with G2677T and the alleles of Ex-76 T/A formed major haplotypes with G2677T and C3435T.[14] We hypothesized that a similar polymorphism will be found in patients with CoA deposition as the polymorphism predisposes the hippocampal neuronal and glial cells to seizure-induced excitotoxic damage and CoA formation ensues as a buffer response. Here, PGP is linked to renal carcinoma.