Determination of aldehyde dehydrogenase phenotypes using hair roots: re-examination.

The method for determination of human aldehyde dehydrogenase (ALDH) phenotypes by isoelectric focusing of hair root extracts was re-examined. In order to cancel irregularities stemming from various factors which are not related to the ALDH abnormality and to obtain reproducible results, the sample size for isoelectric focusing should be adjusted using mitochondrial malate dehydrogenase or isocitrate dehydrogenase as an internal reference.