The means ± SEM of the relative KCC2 mRNA levels of the cirrhotic patients with grade I–II HE (0.0034±0.0011; n=29) were significantly lower (P<0.05, Fig. 1) than those of the cirrhotic patients without HE (0.0045±0.0023; n=20) or those of the healthy individuals (0.0055±0.0023; n=15). This evidence concerns the gene SLC12A5 and hereditary elliptocytosis.