Unique sequences of human DNA were hybridized with cellular RNA to estimate the fraction of DNA transcribed. Approximately 2.5% of the unique sequences were represented in the RNA of various types of leukemic leukocytes, liver, and kidney. The fraction of DNA transcribed in cultural normal lymphocytes and HeLa cells was significantly higher than that obtained with cells from leukemia patients.


This research was supported by Grant NP-125 from the American Cancer Society, Grant DRG 1061 from the Damon Runyon Memorial Fund, and Grant G-267 from the Robert A. Welch Foundation.

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