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laboratory using quantitative methods, that certain amino
acids in leukemic blood are always elevated. Paper chroma-
tographic methods have shown that leukemic patients' blood
contains more glutamic acid, phenylalanine, and leucine.
Adult patients with chronic myelogenous and chronic lymphatie
leukemia also had elevated levels of glutamic acid and phenyl-
alanine. This was an interesting quantitative bit of informa-
tion which allowed us to embark on a new line of investigation
dealing with the role of phenylalanine and glutamic acid and
their metabolism in the body of leukemic patients*
In a paper concerned with the enzymes dealing with glutamic
acid, Dr. Waisman and his associates, Carl Monder and J. N.
Williams, Jr. showed that the white blood cells of patients
with leukemia contained much more of this enzyme than white
cells from normal patients. The glutamic-oxalacetic trans-
aminase level of white cells were similar in both leukemic
and normal individuals.
Dr. Waisman made the observation earlier that hyper-
pigmentation developed in the skin of patients treated with
antifolic drugs for a long time so that white children became
noticeably darker if they survived for as long as a year.
Proof of the increased melanin pigment in the skin was obtained
by appropriate pathological sections of the skin. Since it
was known that phenylalanine was high in the blood and that
phenylalanine was a precursor for malanin formation, it was
necessary to obtain a better understanding of how phenylalanine