Limit of genetic disorder

• Genetic tests are not available for every possible inherited disorder
• Genetic tests are not completely reliable
• Genetic tests may produce false positive or false negative results
• False positives:

  • A genetic test that wrongly detected a certain allele or faulty chromosome
  • The individual could believe they have inherited a genetic condition when they have not
• False negatives:

  • A genetic test that has failed to detect a certain allele or faulty chromosome
  • The parents may be given incorrect results
• Gene therapy involves inserting copies of a normal allele into the chromosomes of an individual who carries a faulty allele
• Gene therapy is not always successful
• Research is continuing to develop gene therapy further
• Problems in the gene therapy process:

  • Alleles may not go into every target cell
  • Alleles may be inserted into chromosomes in random places, not in the required position
  • Some treated cells may be replaced naturally by the patient's own untreated cells
• Different methods to get alleles into patient's cells:

  • Using nose sprays
  • Using modified cold viruses
  • Direct injection of DNA
• Gene therapy can have major ethical implications in society
• Some people disagree with gene alteration in people, believing it is unnatural
• Others think gene therapy prevents unnecessary suffering in affected individuals
• Gene therapy only affects the individual involved, not future generations likely to inherit similar diseases