Intermediate phenotype analysis of patients, unaffected siblings, and healthy controls identifies VMAT2 as a candidate gene for psychotic disorder and neurocognition

Simons CJ, van Winkel R, Schizophr Bull 2013 Jul;39(4):848-56 PMID: 22532702 Abstract Psychotic disorders are associated with neurocognitive alterations that aggregate in unaffected family members, suggesting that genetic vulnerability to psychotic disorder impacts neurocognition. The aim of the present study was to investigate whether selected schizophrenia candidate single nucleotide polymorphisms (SNPs) are associated with (1) neurocognitive functioning across populations at …

Simons CJ, van Winkel R, Intermediate phenotype analysis of patients, unaffected siblings, and healthy controls identifies VMAT2 as a candidate gene for psychotic disorder and neurocognition

The association between social anhedonia, withdrawal and psychotic experiences in general and high-risk populations

Velthorst E, Meijer C, Schizophr. Res. 2012 Jul;138(2-3):290-4 PMID: 22484023 Abstract BACKGROUND: Social anhedonia (SA) and withdrawal are clinically relevant phenomena in schizophrenia. To examine the nature of the overlap between SA, withdrawal and positive symptoms, we investigated whether the co-occurrence of these phenotypes is more prominent in siblings of patients with a psychotic disorder compared to healthy controls, and …

Velthorst E, Meijer C, The association between social anhedonia, withdrawal and psychotic experiences in general and high-risk populations

Age at onset of non-affective psychosis in relation to cannabis use, other drug use and gender

Dekker N, Meijer J, Koeter M, van den Brink W, van Beveren N, Kahn RS, Linszen DH, van Os J, Wiersma D, Bruggeman R, Cahn W, de Haan L, Krabbendam L, Myin-Germeys I, Psychol Med 2012 Sep;42(9):1903-11 PMID: 22452790 Abstract BACKGROUND: Cannabis use is associated with an earlier age at onset of psychotic illness. The aim of the present study …

Dekker N, Meijer J, Koeter M, van den Brink W, van Beveren N, Kahn RS, Linszen DH, van Os J, Wiersma D, Bruggeman R, Cahn W, de Haan L, Krabbendam L, Myin-Germeys I, Age at onset of non-affective psychosis in relation to cannabis use, other drug use and gender

Genetic Risk and Outcome of Psychosis (GROUP), a multi-site longitudinal cohort study focused on gene-environment interaction: objectives, sample characteristics, recruitment and assessment methods

Korver N, Quee PJ, Boos HB, Simons CJ, de Haan L, Int J Methods Psychiatr Res 2012 Sep;21(3):205-21 PMID: 22419500 Abstract OBJECTIVE: A longitudinal focus on gene-environment vulnerability and resilience in both patients, their unaffected family members and non-related controls offers the opportunity to elucidate etiological and pathogenetic factors influencing the onset and course of psychotic disorders. The current paper …

Korver N, Quee PJ, Boos HB, Simons CJ, de Haan L, Genetic Risk and Outcome of Psychosis (GROUP), a multi-site longitudinal cohort study focused on gene-environment interaction: objectives, sample characteristics, recruitment and assessment methods

Social cognition and quality of life in schizophrenia

Maat A, Fett AK, Derks E, Schizophr. Res. 2012 May;137(1-3):212-8 PMID: 22406280 Abstract Schizophrenia is associated with poor quality of life (QOL). Whereas the effects of neurocognitive deficits and psychopathology on QOL of schizophrenia patients have recently been elucidated, little is known about social cognitive deficits in this regard. This study investigated the influence of social cognition on QOL in …

Maat A, Fett AK, Derks E, Social cognition and quality of life in schizophrenia

Clinical response to antipsychotic drug treatment: association study of polymorphisms in six candidate genes

Vehof J, Burger H, Wilffert B, Al Hadithy A, Alizadeh BZ, Snieder H, Eur Neuropsychopharmacol 2012 Sep;22(9):625-31 PMID: 22386772 Abstract Pharmacogenetic studies have demonstrated significant associations between several candidate genes (DRD2, DRD3, 5HTR2A and 5HTR2C, COMT and MTHFR) and antipsychotic drug response. The present study investigates the effect of nine polymorphisms in these genes for an association with antipsychotic treatment …

Vehof J, Burger H, Wilffert B, Al Hadithy A, Alizadeh BZ, Snieder H, Clinical response to antipsychotic drug treatment: association study of polymorphisms in six candidate genes