Biological Explanation: Genetic inheritance

Ripke et al (2014)

Reported 108 genetic variants that could mediate a vulnerability to the disorder, including variations of the 8 and 11 chromosomes and the C4 gene

-Link to the genetic predisposition to schizophrenia through the inheritance of certain faulty genes, biochemical imbalances or brain structure abnormailities

Hong et al (2001)

Found that a variation of the gene TPH was far more common with Chinese patients with schizophrenia

-Ethnocentric

Gottesman & Shields (1991)

A meta-analysis of 40  twin studies, found that schizophrenic patients who share a 100% genetic similarity have a 48% chance of developing the disorder

1% of general population have schizophrenia

Found that as genetic similarity decreased so did the likelihood of inherited schizophrenia, with 1st degree relatives ranging from 6-17%, 2nd degree relatives ranging from 5-6% and 3rd degree relatives ranging from 2-4%

Tienari (1991)

Found that if the biological mother had a history of schizophrenia, the chance of gaining schizophrenia, even if removed from family, was 10%

If the biological mother did not have a history of schizophrenia the general rate of 1% stayed

Strong evidence that genetics do play a part as the influence of the environment in this study was heavily controlled

Evaluation points

• Research support: Tienari

• Alternative explanations

• Biologically reductionist

• Cause and effect

• Psychology as a science