Lecture 19

Question 1

What is the genetic influence to lifespan

Answer 1

Genetic variation in “longevity” genes may influence lifespan

Question 2

What are single nucleotide polymorphisms (SNPs)

Answer 2

Difference in inside DNA building block (nucleotides)

Question 3

How common do SNPs occur

Answer 3

1:300 nucleotides

Question 4

What do SNPs cause

Answer 4

• Polymorphic changes
• Major source of genetic variation

Question 5

What is polymorphism

Answer 5

• Phenomenon describing existence of compound in 2+ forms
• DNA sequence variation common in population

Question 6

What is nutritional genomics

Answer 6

Science studying relationship between human genomes and human nutrition and health

Question 7

Explain the potential effects of nutrition in different genotypes

Answer 7

If 3 people had the exact same diet:
– Genotype one would show improvement in health
– Genotype two would show no effect in health
– Genotype three would show impairment in health

Question 8

What causes an increase in inflammatory cytokines

Answer 8

Aging

Question 9

What disorders are an increase in cytokines related to

Answer 9

Alzheimer’s, cardiovascular disease, arthritis

Question 10

What is interleukin (IL-6)

Answer 10

• Inflammatory cytokine
• Regulate white blood cells

Question 11

What is interleukin positively correlated with

Answer 11

Greater mortality

Question 12

Is SNP the promoter of IL-6

Answer 12

Yes
- Increases IL-6 levels and mortality rate

Question 13

What does it mean to be the promoter

Answer 13

A promoter is a region of DNA that initiated transcription of a particular gene

Question 14

What genes does the mitochondria contain

Answer 14

Components of the ETC

Question 15

How common is damage to the mitochondrial genome vs nuclear genome

Answer 15

Damage to the mitochondria occurs 10x more frequently

Question 16

What causes damage to the mitochondria

Answer 16

Generation of reactive oxygen species (ROS)

Question 17

What are ROS’s

Answer 17

Highly reactive chemical species containing oxygen

Question 18

What are examples of ROS’s (4)

Answer 18

1. Peroxides
2. Superoxides
3. Hydroxyl radical
4. Singlet oxygen

Question 19

What happens to the replication process as we age

Answer 19

• Errors in replication become more frequent
• Accumulating mutations in mitochondrial DNA accelerate aging

Question 20

What is the role of DNA polymerase gamma

Answer 20

Replicates and proof reads/ repairs mitochondrial DNA

Question 21

What happens to DNA polymerase gamma as we age

Answer 21

Becomes less effective

Question 22

What did the study of mice and mitochondrial mutations prove

Answer 22

• There is a causative link between mutations in mitochondrial DNA and aging phenotypes
• Mice with mutations showed accelerated evidence of aging by 25 weeks

Question 23

How can exercise reduce effects of aging

Answer 23

Increased muscle and brain weight shows increased DNA polymerase gamma, correcting mitochondrial mutations

Question 24

What are the effects of caloric restriction on animals

Answer 24

Extended healthy lifespan

Question 25

What is caloric restriction

Answer 25

20-40% reduction in daily energy intake, without malnutrition

Question 26

What are the effects of caloric restriction on humans

Answer 26

Inconclusive evidence

Question 27

In a diabetes prevention study, were the use of drugs or lifestyle modifications more helpful

Answer 27

Diabetes was best prevented by lifestyle intervention