Twin and Adoption studies Flashcards
(18 cards)
How much DNA do Monozygotic (Mz) twins share?
100%
How much DNA do Dizygotic (Dz) twins share?
50%
What are Mz twins?
identical twins
What are Dz twins?
non-identical
How do we conduct twin studies?
we find a set of twins where at least one has a specific characteristic, e.g., having schizophrenia.
We conduct studies to see how likely it is that if one twin has a disorder, that the other will too.
How do we compare concordance rates?
We see how many times the second twin has the same trait and compare to see if there is a genetic element to the characteristic.
Why is using DNA testing a strength?
this can determine whether DNA is shared 50% or 100%. which will affect the genetic outcome.
What issue and debate do twin studies tackle?
whether behaviour is nature or nurture.
What is conducted to calculate whether they are MZ or DZ twins?
several methods such as DNA tests
Why is triangulation of data a strength for twin studies?
We can measure a specific trait in several ways to ensure it is exactly what we think were measuring - increases validity.
Why are twin studies not generalisable?
Twins are very rare in the population.
Why were twin studies historically less accurate?
There was no DNA testing so it was hard to determine with certainty whether twins were MZ or DZ.
What is an adoption study?
We study a specific behaviour by looking at an adopted child and comparing their characteristics to their biological parents and their adoptive parents.
How do we conduct an adoption study?
Researchers look at the frequency with which a trait occurs in children who live with a biological parent of the same trait
They then compare this with the rates of children who live with adoptive parents without that trait.
They look at the differences in frequency between the groups.
What key issue and debate that adoption studies aim to answer?
nature vs nurture
what makes adoption studies ethical?
adoption is a naturally occurring event making it not invasive as they are not actively separating children from their parents.
Why are adoption studies time consuming?
Recruiting appropriate adoptive families can take time
Why is it difficult to answer nature vs nurture from adoption studies?
because they do not account for prenatal care.
