Flashcards on Mendelian Genetics and Epigenetics
Mendelian Genetics and Epigenetics: A Comprehensive Guide
Tap to flip · Swipe to navigate
Epigenetics
23 cards
Card 1
Question: What is the difference between genetic inheritance and epigenetic inheritance?
Answer: Genetic inheritance: changes in DNA nucleotide sequence passed between cells/generations. Epigenetic inheritance: information inherited that does not
Card 2
Question: How do the authors Cavalli and Heard define epigenetics in this review?
Answer: The study of molecules and mechanisms that can perpetuate alternative gene activity states in the context of the same DNA sequence.
Card 3
Question: Give two historical definitions of epigenetics from Waddington and Bird.
Answer: Waddington: processes by which the genotype brings the phenotype into being. Bird: structural adaptations of chromosomal regions to register, signal o
Card 4
Question: What special cases of epigenetic inheritance are mentioned?
Answer: Asymmetric cell division and maternal contribution.
Card 5
Question: What discovery demonstrated position effects on gene expression in flies?
Answer: Inversion of the White locus into heterochromatin caused the gene to be silenced in clones of cells, producing white rather than red eyes despite unch
Card 6
Question: Name four carriers of epigenetic information described in the content.
Answer: 1) Heterochromatin components (e.g., H3K9me3, HP1) 2) Polycomb proteins (e.g., H3K27me3, H2AK119ub) 3) Noncoding RNA (e.g., Xist) 4) DNA methylation (
Card 7
Question: What histone modification and proteins are associated with heterochromatin-based epigenetic inheritance?
Answer: Histone H3K9 trimethylation catalyzed by SUV39 and SETDB1, and bound by HP1 which can self-propagate.
Card 8
Question: How do Polycomb proteins contribute to epigenetic regulation?
Answer: They are recruited by DNA-binding proteins and/or noncoding RNAs and mediate H3K27 trimethylation and H2AK119 ubiquitination to repress gene expressio
Card 9
Question: How can noncoding RNAs mediate epigenetic repression?
Answer: Noncoding RNAs are recruited to genomic target sites and repress gene expression via Polycomb proteins or by promoting DNA methylation; example: X-chr
Card 10
Question: Describe the maintenance mechanism of CpG island methylation during DNA replication.
Answer: After replication a CpG island becomes hemi‑methylated; a maintenance enzyme recognizes this and methylates the unmethylated cytosine to re-establish