It is known that there is a great deal of tests for rapid DNA sequencing and genotyping. But what is not known, is that these tests have resulted in identification of some of the individual genetic variations of which contribute to success in athletic performance (Lippi,G et al; 2009.) The genetic make up of particular physical performance phenotypes could be the explanation behind an athlete’s success (Lippi,G et al; 2009.) These phenotypes include; endurance capacity, muscle performance, and the ability of tendons and ligaments to withstand injury. It is hoped that genetic research in sports will help to clarify several aspects of human biology and physiology (Lippi,G et al; 2009.) Further hoping to be able to explain how exercise training regulates the expression of genes of which encode various enzymes in muscle and other tissue.
As of yet, finding the relevant gene that coincides with human athletic performance has been difficult. However, a few genetic traits have been found that lead to the success in endurance ability. These traits consist of increased mitochondrial enzyme activity and the discovery of a family of proteins called “hypoxia inducible factors” (Lippi,G et al; 2009.) These inducible factors have found to enhance the response to hypoxia of which occurs in the tissues dealing with increased oxygen demand (Lippi,G et al; 2009.) This is beneficial to athletes as their muscles are working at a higher intensity. The discoveries of gene polymorphisms have also found to be associated with sport performance. However, as this is a new field of scientific inquiry the results are still subjective. These polymorphisms are within the table seen below. An example of these polymorphisms is within the PPAR- delta, of which regulates expression of genes involved in lipid and carbohydrate metabolism (Lippi,G et al; 2009.) It contains a functional polymorphism of which is associated with the success of endurance performance (Lippi,G et al; 2009.)
Gene Polymorphisms – Sport Performance
· PPAR gene
· Alpha2a-adrenceptor gene
· Bradykinin beta 2 receptor
· Endothelial nitric oxide synthase 3 genes
(Lippi,G etal.; 2009)
Through antibody staining, ATPase staining and electrophoresis it has been found that four major fiber types exist in mammalian skeletal muscles (Lippi,G et al; 2009.) Three of these take a fast contracting form (FT) and the other is slow contracting (ST) (Lippi,G et al; 2009.) As FT fibers are related to power and speed capacity, sprinters have been recently found to have a high proportion of these fibers. To aid in the regeneration of ATP, of which is a requirement for athletes as a result of intense muscle contraction of FT fibers, the Creatin Kinase Isoenzyme gene - encodes the cytosolic muscle isoform, of which rapidly regenerates ATP (Lippi,G et al; 2009.)
Different genotypes at a single locus have also been observed in studies of the gene encoding Antiotensin – converting enzyme (ACE). The results of these observations have found beneficial effects on athletic performance (Lippi,G et al; 2009.) It has been discovered the ACE gene has two alleles, a deletion allele and an insertion allele. Some variation in the ACE gene may be associated with heritable traits including physical and physiological skill parameters and physical performance (Lippi,G et al; 2009.) For example, in endurance athletes the insertion allele has been found at an increased frequency and the deletion allele has been found within elite sprint athletes (Lippi,G et al; 2009.)
By having an understanding of the relationship between genetic structure and success in athletic ability it can potentially lead to great things. It can aid in the development of genetic performance tests, be able to identify those of who are going to benefit medically from exercise programs as well as preventing sudden deaths in sport by having a greater understanding of the genetic makeup of an elite athlete (Lippi,G et al; 2009.) However, as this is a reasonably new field of genetic study there is still a lot more to discover.
For further information on this topic check out the site; http://www.bmboxfordjournals.org/
By Jacqueline Nightingale