Epigenetics & Genomics

Question 0

Transposons

Answer 0

LINES & SINES
DNA sequences that can change their location within the gnome

Transposons as jumping genes‖ may integrate into critical spot in the genome, disrupt a gene, and cause disease

Transposons as repetitive sequence may lead to
misalignment during meiosis and gene disruption (cross-over)

Question 1

Pseudogenes

Answer 1

Duplication in the human genome

1. Vestigeal: Genes no longer transcribed ex)Vitamin C gene
2. Duplicated: One gene not expressed, but a similar gene is. ex) beta globin genes
3. Processed: processed RNA reverse transcribed into new chromosomal site.

Question 2

Haplotype

Answer 2

A haplotype is a combination of alleles at different chromosomal loci that are transmitted together.

A haplotype may be one locus, several loci, or an entire
chromosome depending on the number of recombination events that have occurred between a given set of loci.

Question 3

DNA Methylation

Answer 3

methyl group added to 5’ position of cytosine

Question 4

Methylation inheritance process (protein specific)

Answer 4

1) Dmnt3 methylates DNA
2) MeCP2 recruits HDAC to deacetylate histones
3) Replication - only parent strand remains methylated
4) McCP2 recruits Dmnt3 to methylate newly synthesized strand
5) MeCP2 deacetylates new strand

Question 5

ICF Syndrome

Answer 5

Immunodeficiency-centromeric instability-facial anomalies syndrome

Defect in Dnmt3b gene

facial dysmorphism, mental retardation, recurrent and prolonged
infections, and variable immune deficiency with a constant decrease of IgA.

Question 6

Beckwith-Wiedemann Syndrome (BWS)

Answer 6

• maternal chromosomal rearrangements of 11p15(imprinted region)
• paternal uniparental disomy (UPD)
• abnormal methylation at 11p15

Enlarged tongue, ear creases or pits, abdominal wall defects, neonatal hypoglycemia, increased cancer risk. Increased birth weight

Question 7

PEGylation

Answer 7

Used in protein replacement therapies for treatment of certain genetic disorders.

Proteins linked with polyethyline glycol that reduces degradation, clearance, and immune responses the protein therapy cause.

Question 8

Gendicine

Answer 8

Uses an adenovirus as a vector for p53. Virus is injected directly into the tumor, reinstating endogenous production of p53 from cells that lost it during cancer progression

Treatment of head and neck squamous cell carcinomas