This paper suggests that about 8% of Caucasians are genetically deficient
in a particular enzyme which helps metabolize MDMA, and that such
individuals may be particularly sensitive to its effects and "at increased
risk of acute toxicity". However, these same people "may be less
susceptible to the chronic neurological effects of the drug".
[I asked two senior American researchers for their opinions on the paper.
One commented "I think he has a point". The other said "It is a nice study
in terms of showing a pathway of MDMA metabolism that can be applied to the
human condition. Unfortunately, we cannot predict whether 'poor
metabolizers' will be more (or less) susceptible to acute toxic (i.e.
predominantly hyperthermia) much less the chronic neurological effects
('neurotoxicity'), because we do not yet know which metabolites are
responsible for the acute and/or neurochemical (neurological) effects of
the compound. Tucker et al. allude to this in the final paragraph. The data
do show, however, that genetic differences in metabolism or MDMA may be
responsible for differences in the response to the drug (toxic or