genetics - sport science

12.1 Role of Genes in Inheritance of Human Characteristics

  • Genes are sections of DNA found on chromosomes.

  • DNA replicates during cell division to pass on genes to new cells.

  • Children inherit genes from parents via sex cells (gametes): 50% from mother, 50% from father.

  • Many combinations of genes are possible from the same parents.

  • Human characteristics (phenotype) are determined by their genes (genotype).

  • Some characteristics expressed developmentally by genes (e.g., eye color, gender) while others require environmental factors (e.g., height, VO2 max).

12.2 Influence of Genes on Human Characteristics

  • Genes code for proteins essential for individual development.

  • Genes can be switched on or off based on internal/external factors.

  • Certain characteristics may change throughout a person's lifetime.

  • Genes determine heritable characteristics unique to each individual.

12.3 Contribution of Genetic and Environmental Factors on Performance in Sports

Genetic Factors Influencing Performance:

  • Height

  • Muscle fiber type

  • Anaerobic threshold

  • Lung capacity

  • Flexibility

Environmental Factors Influencing Performance:

  • Physical training

  • Nutrition

  • Technological aids

  • Climate

  • Elite athletes distinguished by both inherited characteristics and training history.

  • It is currently difficult to quantify the relative contribution of genetics versus training for elite performance.

12.4 Implications of Genetic Screening for Sports, Exercise, and Health

Advantages:

  • Identification of life-threatening conditions (e.g., risk of sudden cardiac death, connective tissue disorders).

  • Prediction of injury susceptibility to improve athlete safety.

Disadvantages:

  • Cost and accessibility may lead to inequality (only available to the wealthy).

  • Ethical concerns regarding involuntary exclusion from sports.

  • Risk of gene doping for enhanced performance.

  • Potential damage to the overall gene pool.