genetics & society Flashcards
define eugenics
the practice of improving the human species by selectively mating people with specific desirable hereditary traits. It aims to reduce human suffering by “breeding out” disease, disabilities and so-called undesirable characteristics from the human population.
what is the difference between positive and negative eugenics
positive eugenics refers to efforts aimed at increasing desirable traits, while negative eugenics refers to efforts aimed at decreasing undesirable traits
what is genetic counselling
the process by which patients or relatives at risk of a disorder that may be hereditary are advised of the;
- consequences of the disorder
- the probability of developing or transmitting it
- the ways in which this may be prevented or ameliorated
what is directive genetic counselling
- doctor knows best approach
- family may not understand full consequences
- family may expect to be directed
- duty to reduce disease frequency
what is non directive genetic counselling
- aim of counselling is primarily to help the individual
- family may have extensive personal experience
- decisions on reproduction must be personal
- directive advice may be counterproductive
what is a screening test
the process of identifying people with an increased chance of a condition
someone who is screen positive may not have the condition
what is a diagnostic test
confirms whether the condition is present or not
what are 4 ways of measuring the outcome of genetic counselling
- measure number of pre natal tests done
- measure number of pre natal tests not done
- measure how much people remember
- reduction in the prevalence of certain diseases?
what is non invasive prenatal testing (NIPT)
method of determining the risk that the fetus will be born with certain genetic abnormalities. This testing analyzes small fragments of DNA that are circulating in a pregnant woman’s blood.
these fragments are free-floating and not within cells, and so are called cell-free DNA
when is NIPT usually used
to look for chromosomal disorders that are caused by the presence of an extra or missing copy (aneuploidy) of a chromosome
primarily looks for :
- Down syndrome (trisomy 21, caused by an extra chromosome 21),
- trisomy 18 (caused by an extra chromosome 18),
- trisomy 13 (caused by an extra chromosome 13), extra or missing copies of the X chromosome and Y chromosome (the sex chromosomes).
The accuracy of the test varies by disorder.
what are ethics regarding NIPT
- free informed choice
- the government has a duty to eliminate mate or reduce harm from the intervention
- policies address prejudice, bias and discrimination
- public money is spent fairly
what are invasive tests
either involve taking a sample of amniotic fluid or placental tissue from the womb. The procedure carries a small risk of miscarriage due to the removal of a small sample of cells from amniotic fluid around the foetus.
what are concerns about eugenics
- subtle pressure
- routinization of testing ie not fully informed consent
- society valuing disabled children adults
- isolation of families
- disapproval by society of continuing a pregnancy after screening
what are molecular tests
- look for changes in one or more genes
- determine the order of DNA building blocks (nucleotides) in an individual’s genetic code, a process called DNA sequencing
types of molecular tests
- Targeted single variant
- single gene
- gene panel
- Whole exome sequencing/whole genome sequencing
