Epigenetics and Disease Flashcards
Histone
Protein around which DNA winds
Transcription
Process of making mRNA from a section of DNA
Chromatin
Proteins and DNA in the nucleus
Gene
Section of DNA that carries the code for a protein or non coding RNA
Epigenetics
Regulation of gene expression not caused by altered DNA sequence
DNA methylation leads to
silencing of genes
Imprinting
The process of predictable gene silencing on one copy of a chromosome but not on the other, depending on which parent transmits the chromosome.
Epigentic modification _____ maintained in successive mitotic cell divisions
are
Carries the code for a protein to a ribosome
mRNA
Can regulate gene expression
miRNA
Some epigenetic modifications can be
reversed
Abnormal methylation of tumor-suppressor genes may be a factor in ____________ of specific types of cancer
progression
A gene that has methylation in its ________ region is less likely to be transcribed into mRNA
promoter
Oncomirs
MicroRNAs that stimulate development and progression of cancer
Housekeeping genes
Genes that are necessary to maintain function of all types of cells and that normally remain transcriptionally active
Epigenetic transgenerational inheritance
Hereditary transmission of epigenetic changes to successive generations
Environmental chemicals, dietary factors, and alcohol intake can modify gene expression by causing
Epigenetic modifications
Causes of Prader-Willi syndrome
Chromosomal deletion on the chromosome 15 inherited from the father. Typically that section of the gene is read only on the chromosome that is inherited from the father and not on the chromosome inherited from the mother
In Prader-Willi syndrome, which copy of the crucial genes is imprinted
The genes on the chromosome inherited from the mother are imprinted (transcriptionally silenced). Because those same genes are deleted from the chromosome inherited from the father, no products are produced from those genes during development, causing Prader-Willi syndrome.
Does imprinting of these genes occur normally, or is this an abnormal occurrence
Imprinting of these genes on the mother’s chromosome is normal. The deletion of those genes fromt he father’s chromosone is abnormal
