genetic screening

• genetic screening

  • determine if individuals have particular alleles in their genome eg alleles causing disorders
  • 3 main uses:

  -identify individuals who are carrying an allele at gene locus for disorder

  -screening of embryo prior to implantation

  -testing foetus before birth(prenatal testing)
• identification of carriers

  • offered to individuals with history of genetic disorders
  • couples tested prior to having children to determine probability of children inheriting disorder
• prenatal testing

  • offered to pregnant women
  • eg chronic villus sampling of embryo/foetus in uterus

  -test sample of cells from placenta using fine needle

  -cells contain foetal DNA, analyses for genetic disorders

  -1/2% risk of miscarriage
• social and ethical issues

  • emotional stress
  • false positives or negatives due to inaccuracy
  • may lead to designer babies- selecting embryos with certain traits eg blue eyes
  • prenatal testing- risk of miscarriage, false positive results=termination of health foetus, ethical implications if abortion involved