Ethnic differences in the frequency of distribution of serum cholinesterase activity in the Iranian population.

One thousand Iranians belonging to 5 different Iranian ethnic groups were tested for butyrylcholinesterase (BChE) activity and phenotype. The phenotype was measured as percent inhibition in the presence of dibucaine. It was found that the Iranian population had an extraordinarily high frequency of the atypical variant of butyrylcholinesterase.