Genetic Basis of Athletic Capability

Question 1

Define phenotype?

Answer 1

The physical expression of the genes, a consequence of the interaction of the genotype with the physical environment.

Question 2

What is an athletic phenotype?

Answer 2

Occurs where an ‘athletic genotype’ interacts with appropriate environmental stimuli to produce high-level performance in the chosen physical activity. Ie. nature and nurture.

Question 3

What do many believe is the most important facet for athletic capability?

Answer 3

Genetic predisposition.

Question 4

What is closely linked to endurance exercise performance?

Answer 4

VO2max

Question 5

What is VO2max dependent on?

Answer 5

A number of factors including pulmonary, circulatory and muscle function.

Question 6

What did Holloszy observe in 1967?

Answer 6

That muscle oxidative enzyme activity adapted in repos e to exercise training. Therefore not only genetic but adaptive also.

Question 7

What is the difference between HCR and LCR in endurance performance?

Answer 7

HCR is > 300% greater.

Question 8

What is the difference between skeletal muscle I’m HCR and LCR?

Answer 8

~35% greater in HCR. LCR has ~35% smaller muscle fibre area and a greater capillary density.

Question 9

How is citrate synthase and b-HAD activity different in HCR and LCR?

Answer 9

~40 % greater in HCR.

Question 10

How is PFK activity different in HCR vs. LCR?

Answer 10

~30% lower in HCR.

Question 11

How does VO2max vary in HCR and LCR?

Answer 11

~50% greater in HCR vs LCR

Question 12

What did LCR show?

Answer 12

Increased mean arterial blood pressure, decreased arterial responsiveness, increased FFA (94%), increase circulating triglycerides (168%), increased circulating insulin (131%) and increases fasting blood glucose (20%). Decreased peroxisome proliferative activated receptor g and co activator 1a. Decreased ATP synthase H-transporting to mitochondria F1 complex.

Question 13

What is an essential component of Darwin’s concept of the survival of gene pools?

Answer 13

Ability to adapt

Question 14

What was a key environmental factor present during human evolution?

Answer 14

Exercise

Question 15

Why could a change in gene-environment interaction help explain?

Answer 15

Modern maladaption to chronic inactivity and chronic diseases.

Question 16

What is the ACE gene?

Answer 16

An angiotensin converting enzymes which converts Ang1 to Ang2.

Question 17

What is Ang2?

Answer 17

A potent vasoconstrictor, therefore important I’m regulating blood flow and pressure. It increases bradykinin breakdown.

Question 18

What is bradykinins role?

Answer 18

Stimulating bold flow, glucose extraction, muscle protein synthesis and aids efficiency.

Question 19

What is renins role in the angiotensin system?

Answer 19

It is releases from the kidney under conditions of salt, blood volume loss and sympathetic NS. Cleaves angiotensingenin to produce angiotensin 1.

Question 20

What is a common polymorphism in the ACE gene?

Answer 20

A 287 base sequence insertion or deletion.

Question 21

What is the deleted allele of ACE associated with?

Answer 21

Greater ACE activity.

Question 22

What is homozygous inserted (II) ACE associated with?

Answer 22

A greater anabolic and efficiency response to training than those with ID/DD ACE. ‘Better training ability’

Question 23

What do ACE inhibitors do?

Answer 23

Reduce circulating ACE and therefore have an analogous effect to that of I (insertion) allele expression. They may relate to energy conservation therefore increased efficiency under conditions of reduced nutrient and/or oxygen to flow to the periphery.

Question 24

What do athletic activity and health show?

Answer 24

Strong correlation which suggest research studies should use active populations as their controls.

Question 25

Compare selective breeding and trainings effects on athletic ability?

Answer 25

Both can increase but training has a greater effect.

Question 26

What does exercise do to skeletal muscle mechanical signals?

Answer 26

Converts them into a molecular response.

Question 27

What are the molecular responses does exercise cause on skeletal muscle?

Answer 27

Increases phosphorylation of TF, increased mRNA synthesis/protein synthesis, inducing a phenotypic adaptation.

Question 28

Define genotype?

Answer 28

The genetic make-up of an individual.