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NCI Dictionary of Genetics Terms

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5 results found for: E



  • epigenetic alteration  listen  (EH-pih-jeh-NEH-tik ALL-teh-RAY-shun)
    A heritable change that does not affect the DNA sequence but results in a change in gene expression. Examples include promoter methylation and histone modifications. Also called epimutation.

  • epigenetics  listen  (EH-pih-jeh-NEH-tix)
    The study of heritable changes that do not affect the DNA sequence but influence gene expression.

  • epimutation  listen  (EH-pih-myoo-TAY-shun)
    A heritable change that does not affect the DNA sequence but results in a change in gene expression. Examples include promoter methylation and histone modifications. Also called epigenetic alteration.

  • ER-negative PR-negative HER2/neu-negative breast cancer  listen  (... NEH-guh-tiv ... NEH-guh-tiv ... NEH-guh-tiv brest KAN-ser)
    ER-negative PR-negative HER2/neu-negative breast cancer is defined by a lack of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2/neu). Also called triple-negative breast cancer.

  • exon  listen  (EK-son)
    The sequence of DNA present in mature messenger RNA, some of which encodes the amino acids of a protein. Most genes have multiple exons with introns between them.