Topic 12 - Genetics

• Chromosomes are made up of deoxyribonucleic acid (DNA) sections which are referred to as genes
• Children inherit genes from their parents via sex cells (gametes) with 50 % from the mother and 50% from the father, a child receives 2 genomes.
• Inheritense is the process where genetic information is passed from parent to child.
• Phenotype: the physical expression of a trait as a result of genes
• Genotype: The genetic makeup of an organism
• Some characteristics are expressed developmentally by genes (e.g. eye colour, gender) while others require an environmental switch (e.g. height, Vo2max)
• Potential athletic ability will be higher if both parents had potential higher athletic abilities
• Genes code for the production of proteins which are responsible for the development of an individual, they are invovled with many characteristics like height, lung capacity, fast-twitch fibres.
• Genes can be switched on or off depending on internal or external factors,so characteristics influencing athletic performance can change during a person's lifetime. e.g. correct or incorrect diet will influence the growth of an individual.
• Multiple genes determine the measurable heritable characteristics for each individual so it's highly unlikely that a single or even a few genetic elements are associated with superior athletic performance
• genes affect the potential to perform a skill but characteristics are influenced by multiple genes.
• Genetics can predict a performer's potential but success is also influenced by training. The nature of the sport determines the influence of the genetic factors on performance
• Elite athletes can be distinguished from less-well-performing athletes with respect to both genetic characteristics and training histories.
• Genetic Factors:

  • Height and flexibility: a combination allows for optimal stride length and strength
  • Muscle fibre type : inherited from parents, slow-twitch can enhance an athletes ability in distance running
  • Lung Capacity : higher lung capacity facilitates long distance running
  • Anaerobic threshold
• Environmental factors:

  • Physical Training
  • Nutrition : a balanced diet high in carbohydrates is best for endurance athletes
  • technological aids: timing equipment can improve pacing and performance
  • Climate
• Benefits of genetic screening:

  • the identification of life-threatening conditions such as risk of sudden cardiac death or connective tissue disorder to allow for early treatment
  • the identification of potential for certain sports based on genetic profile
  • the possibility of benefits from pre-selection for more suitable sporting activities e.g. talent identification
  • the potential to predict susceptibility to injury and reduce risk/improve safety for an individual athlete by allowing them to take precautions
• Limitations of genetic screening:

  • ethical implications of involuntary exclusion form, or discrimination in one or more sport
  • ethical implications of discrimination beyond sport e.g. employment
  • it may not pick up more subtle traits e.g. an athletes motivation/determination