Dear Dr. Ren, Thank you for your interest. Unfortunately the project ended some time ago and genetic data was never collected for participants from Utrecht. However, the Amsterdam site has participated in other multi-site projects to study e.g. gene-environment interactions (EU-GEI project: http://www.eu-gei.eu/  & GROUP project: DOI: 10.1002/mpr.1352) in relation to schizophrenia/psychosis risk. Given the number of participants it requires to perform genetic analyses, I suggest you focus on these projects instead.

yes i agree with Tim Ziermans 

excluding perhaps hormonic pressure  and social  pressure around 18 acting as triggers there is not any . the first episode is probabilistic phenomenon amenable to prediction only by statistical methods . this postulate can be tested positively and negatively by finding out the number of first incidents world wide ; they will be the same around 6- 7% irrespective of culture 

ps different disciplines pose  the question for a given problem differently in fact they may formulate the same problem from their predictive p

if the postulate will be correct will be of enormous importance in understanding schizophrenia . ( Evolutionary ) 

 Further Psychosis is an generic epiphenomenon to schizophrenia similar to the one of   fever or other  disturbances in the function of the brain .and should not be used as interchangeable term with schizophrenia The real schizophrenia has five  symptoms ; apathy alternating with explosively . thought disorder . misalignment of thought and feelings . inappropriateness of responses socially and ambivalence in this case coexistence  of positive and negative feeling to a subject plus underlying asocial temperament .the later shared by creative people . evolutionary schizophrenia  should be considered as down side trade off  Early application of EST temporarily correct all that except the underlying temperament