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NCI Dictionary of Genetics Terms

6 results found for: E

epigenetic alteration
(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 epigenetic variant and epimutation.
epigenetic variant
(EH-pih-jeh-NEH-tik VAYR-ee-unt)
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 and epimutation.
epigenetics
(EH-pih-jeh-NEH-tix)
The study of heritable changes that do not affect the DNA sequence but influence gene expression.
epimutation
(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 and epigenetic variant.
ER-negative PR-negative HER2/neu-negative breast cancer
(... 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 TNBC and triple-negative breast cancer.
exon
(EK-son)
The sequence of DNA that is present in the final, mature messenger RNA transcript. Most exons code for amino acids, which link together to form a protein. Most genes are made up of many exons with introns in between them.