Cystic fibrosis

• What is cystic fibrosis?

  A respiratory disease caused by a recessive allele
• cause = a mutation in a specific gene or DNA-> must have homozygous recessive as genotype to have it
• Effects of it?

  Causes Thick, sticky mucus to block the bronchioles of the lungs
• What is used to treat the symptom?

  an inhaler
• How does an inhaler work?

  Sends normal versions Of the gene to the lung tissue so that they can make protein needed to prevent symptoms
• Cons to an inhaler:

  • No guarantee genes will get into lung cells
  • genes Must also then get into nucleus
  • Not permanent-> cells that took up the gene will die and be replaced by cells with mutated allele
• Why do you have to use an inhaler repeatedly?

  cells die
• What’s in an inhaler?

  Normal version (dominant allele) of the gene
• Genes = a section of DNA that codes for a protein
• chromosome = long strands of DNA which contain lots of genes (23 pairs)