Selective Breeding & Genetic Engineering

Selective breeding

• Selective breeding (artificial selection) is humans breeding plants and animals for particular genetic characteristics. It has been done for thousands of years, since the first food crops and domesticated animals
• The steps:
  • Choose parents with the desired characteristic from a mixed population
  • Breed them together
  • From the offspring, select those with the desired characteristic and breed them together
  • Continue over many generations until all the offspring show the characteristic
• Characteristics chosen for usefulness or appearance: disease resistance in crops; animals that produce more meat or milk; dogs with a gentle nature; large or unusual flowers
• The risk: selective breeding leads to inbreeding, which reduces variation, so some breeds are prone to disease or inherited defects, and the population may not survive a new disease