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Medical Term:


Pronunciation: pro'to-on'ko-jen


A gene conserved long on the evolutionary scale present in the normal human genome, that appears to have a role in normal cellular physiology and is often involved in regulation of normal cell growth or proliferation; as a result of somatic mutations, these genes may become oncogenic; products of protooncogenes may have important roles in normal cellular differentiation.

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.