1. Gottesman 1991 By Pooja, Jessica and Shohum

2. Aims To investigate the risk of developing schizophrenia in different types of genetic relatives of a schizophrenic.

3. Procedures Compiled data from 40 family studies from the best Western European studies reported over the past century.

4. Findings

5. Conclusions Risk for cousins (2%) is only slightly greater than the general population risk. Second-degree relatives have a risk of around 5%, while first- degree relatives have a risk close to 10%. With one schizophrenic parent the risk was 6% with two it rose to 46%. Monozygotic twins had a 48% concordance rate. Dizygotic twins had a 17%. Concordance rates in this study are not 100% which can suggest that the cause of schizophrenia may not be entirely genetic and other factors such as the environment and cognition may also play a role in the risk of an individual developing schizophrenia.