Nutrigenomics: Epigenetics

Question 1

What is Histone Acetylation?

Answer 1

Addition of an acetyl group. Methyl group (CH3) bound to carbonyl group

Question 2

What is the effect of acetylation on histones?

Answer 2

Acetylation neutralizes positive charge of histone tails = less binding to negative DNA.

• DNA more accessible
• More transcription (gene activation)

Question 3

What is Deacetylation?

Answer 3

Gene silencing

Question 4

What are Sirtuins?

Answer 4

Protein that deacetylates histones (silencing genes). 7 different sirtuins

Question 5

How are Sirtuin genes/proteins changed?

Answer 5

By lifestyle.

• Calorie restriction
• Exercise
• Alcohol
• Smoking
• Plant compounds

Question 6

What is Resveratrol?

Answer 6

Phenolic compound in wine. Histone Modification

Question 7

Resveratrol and Deacetylation

Answer 7

• Sirtuins
• Removal of acetyl group from histone
• Changes gene expression (silences)
• Linked to health and longevity in specific societies

Question 8

Epigenetics

Answer 8

microRNA

Question 9

What are microRNA?

Answer 9

• Made from own genes or introns (non coding regions)
• Short RNA that binds to mRNA and increases mRNA degradation
• Regulation “above”the gene but based on bases in genes (ATCH)
• Another key component of gene regulation

Question 10

miRNA found in Breast Milk

Answer 10

• microRNAs abundant in human breast milk for the duration of breast feeding
• 442 unique premiRNAs and 602 unique miRNAs found in breast milk exosomes
• miRNAs found in mammal milk is stable at room temp and are resistant to repeated freeze cycles
• —encapsulated in exosomes

Question 11

When are miRNA highest in immune support?

Answer 11

first 6 months of feeding

Question 12

RD role with Nutrigenetics

Answer 12

• Translation of scientific knowledge of how diet affects individual humans
• individualized care

Question 13

RD role with nutrigenomics

Answer 13

• translation of scientific knowledge about how diet affect gene expression
• understanding of mechanism

Question 14

Types of genetic testing

Answer 14

• Research –> decode link between genes and disease
• Direct to consumer genetic testing –> send in DNA sample from saliva (ancestral orgins)
• Health care guided testing–> rare disease and chronic disease

Question 15

Transcriptomics

Answer 15

study of gene expression - RNA

Question 16

Proteomics

Answer 16

study of protein expression

Question 17

Metabolomics

Answer 17

study of metabolites, cell metabolic profiles

Question 18

metagenomics

Answer 18

study of genetic material from environment/microorganisms