bio approach: genetic similarity - kinship study

Question 1

genetic similarity:

Answer 1

refers to the degree of shared genetic material between individuals or populations. it reflects the extent to which individuals inherit genetic variants, or alleles, from a common ancestor or gene pool.

Question 2

role of kinship studies -

Answer 2

kinship studies, have played a pivotal role in understanding the influence of genetic similarity on the transmission of behaviors and disorders within families. by investigating whether certain traits “run in families,” these studies have provided key insights into the potential genetic underpinnings of various conditions.

while less prevalent in modern genetic research, kinship studies remain essential for unravelling the genetic basis of complex traits and disorders.

Question 3

study connected to this?

Answer 3

weissman et al (2005) exemplifies the enduring significance of kinship studies, particularly in elucidating the genetic factors contributing to psychiatric disorders such as Major Depressive Disorder (MDD).

Question 4

weissman et al. (2005) aim -

Answer 4

to study the potential genetic nature of Major Depressive Disorder (MDD) spanning three generations.

Question 5

weissman et al. (2005) sample -

Answer 5

longitudinal research study in which the sample consisted of 161 grandchildren and their parents and grandparents - three generations of families.

original sample of depressed individuals, now the grandparents, was selected from an outpatient clinic specializing in mood disorders.

non-depressed participants were selected from the same local community to serve as a comparison group.

Question 6

longitudinal design -

Answer 6

the study took place over a period of twenty years, during which participants (parents and children) were interviewed four times.

this longitudinal design allowed researchers to track the development of psychiatric disorders across multiple generations over time.

Question 7

data collection -

Answer 7

data on psychiatric disorders was collected from clinicians who were blind to past diagnoses of depression or previous interview data.

children were evaluated by two experienced clinicians, including a child psychiatrist and a psychologist, to ensure reliability of diagnoses.

inter-rater reliability was calculated to ensure consistency in diagnoses between clinicians. the researchers assessed the presence of psychiatric disorders, including MDD, anxiety disorders, and alcohol dependency, in the grandchildren.

Question 8

weissman et al. (2005) results -

Answer 8

MDD - 0.82
Anxiety - 0.65
Alcohol dependency – 0.94.

among the grandchildren of individuals with two generations of major depression (grandparents and parents), there were high rates of psychiatric disorders. by the age of 12, 59.2% of the grandchildren were already showing signs of a psychiatric disorder, with anxiety disorders being the most common.

children had an increased risk of any disorder if depression was observed in both the grandparents and the parents, compared to children whose parents were not depressed.

Question 9

continued.. results -

Answer 9

the severity of a parent’s depression was correlated with an increased rate of mood disorders in the children.

on the other hand, if a parent was depressed but there was no history of depression in the grandparents, there was no significant effect of parental depression on the grandchildren.

this suggests that the presence of depression in the grandparents is an important factor in influencing the risk of psychiatric disorders in the grandchildren.

Question 10

conclusion -

Answer 10

evidence for the genetic basis of psychiatric disorders, in specific the role of genetics in the development of psychiatric conditions in familial transmission.

interplay between genetic and environmental factors in mental health disorders.