CNR2 and chronic hepatitis: In addition, no significant difference in the ALT serum values was observed between subgroups established on the basis of the CB2 variants, most probably due to the fact that of the 253 subjects investigated, 200 were chronic hepatitis patients with increased ALT values and only 53 were PNALT subjects with normal ALT, too small a number to influence substantially the mean ALT levels in the three CB2 subgroups.