Genetic Explanations

Question 1

What is genetics?

Answer 1

-genes consisting of DNA stands
-DNA produces instruction for general + specific physical features
-which may impact psychological features

Question 2

How are family studies related to schizophrenia?

Answer 2

-risk of schizophrenia increases in line with genetic similarity to a relative with the disorder

Question 3

How are candidate genes related to schizophrenia?

Answer 3

-identity them
-appears schizophrenia is polygenic
-most likely genes would code for NT like dopamine

Question 4

What is dopamine?

Answer 4

-a NT that generally has an excitatory effect
-linked to the sensation of pleasure

Question 5

How is dopamine linked to schizophrenia?

Answer 5

-high levels = linked to schizophrenia

Question 6

What did Ripke do?

Answer 6

-combined all previous data from genome-wide studies of schizophrenia

Question 7

What did Ripke find?

Answer 7

-genetic makeup of 37,000 people with schizophrenia compared to 113,000 controls
-108 separate genetic variations were associated with slightly increased risk

Question 8

What is aetiologically heterogeneous?

Answer 8

-different combinations of factors can lead to the condition

Question 9

What did Gottesman find about family studies?

Answer 9

-established schizophrenia is more prevalent among biological relatives with the disorder
-closer degree of genetic relatedness = the greater the risk

Question 10

What was Gottesman’s results for his study?

Answer 10

-found children with 2 schizophrenic parents had concordance rate of 46%
-children with 1 schizophrenic paneer and a rate of 13%
-children with siblings had a rate of 9%

Question 11

What did Joseph find about twin studies?

Answer 11

-pooled data for all schizophrenic twin studies
-showed that concordance rates for MZ twins was 40% and DZ twins 7%

Question 12

What did the blind studies show?

Answer 12

-reported lower rates for MZ than Joseph
-still supports the genetic position as they show a rate that is still higher than DZ

Question 13

What did Tiernari find about adoption studies?

Answer 13

-164 adoptees whose biological mother had schizophrenia
-11 children were also diagnosed of schizophrenia
-control - 197 adoptees whose biological mother didn’t have schizophrenia
-4 children were diagnosed schizophrenia
-showed that genetic liability to schizophrenia had been decisively confirmed

Question 14

What is support to genetics causes of schizophrenia? A03

Answer 14

-Gottesman
-clearly shows similarity + shared risk of schizophrenia are closely related
-adoption studies show that children of schizophrenia sufferers are still at a heightened risk of schizophrenia if adopted into a family with no history
-there is overwhelming evidence for the idea that genetic factors make some people more vulnerable to developing

Question 15

What is a contradiction to genetic causes of schizophrenia? AO3

Answer 15

-doesn’t mean that schizophrenia is entirely caused by genetic functions
-number of factors in the environment associated with the risk
-eg. twin study - never have 100% concordance rate - Joseph showed a 40.4%
-suggests there must be other factors influencing the diagnosis

Question 16

What is an alternative to genetic causes of schizophrenia? AO3

Answer 16

-family dysfunction
-suggests that the environment/family an individual grows up in may cause individuals to develop it
-double blind - suggests children who frequently receive contradictory messages from their parents are more likely to develop
-confusing interactions prevent development of an internally coherent structure of reality
-manifests itself in the long run as symptoms

Question 17

What is an issue and debate to genetic cause of schizophrenia?

Answer 17

-biologically reductionist
-limited as it doesn’t explore other possible explanations when there is strong evidence it is a combo of factors which contribute to development of it
-model tells us very little about how genetics interacts with other factors to develop symptoms