title: T102C polymorphism of serotonin-2A receptor gene in Turkish schizophrenia patients: Association with cognitive impairment and soft neurological signs.
abstract: OBJECTIVE
  Previous studies have shown an association between the T102C polymorphism of the serotonin-2A receptor gene and schizophrenia. In addition, an association of this polymorphism with clinical phenotypes in schizophrenia such as treatment response and cognitive impairment has been observed.
  
  
  METHODS
  In this case-control study conducted in Turkish Caucasians, we compared T102C polymorphism genotype and allele frequencies in 76 schizophrenic patients and 165 healthy controls. We also investigated interaction of this polymorphism with clinical and cognitive variables in patients.
  
  
  RESULTS
  No significant difference was observed in the distribution of the three genotypes (T/T, T/C and C/C) and in the allele frequencies in controls and patients with schizophrenia. No evidence of association was detected at various clinical phenotypes including symptom severity, suicidality, treatment response, age of disease onset, number of hospitalizations and history of violence (in co-dominant, dominant, or recessive models). However, as compared to the C/C genotype, patients with 1 or 2 copies of the T allele were characterized by better stroop test performances and less "motor coordination" soft neurological signs.
  
  
  CONCLUSIONS
  Further research is needed to elucidate the impact of T102C polymorphism on neurocognitive functions in both healthy and patient populations.
authors.affiliation: Department of Psychiatry, Bolu İzzet Baysal Medical School, Bolu, Turkey.
authors.forename: Adnan
authors.initials: A
authors.lastname: Özçetin
authors.affiliation: Department of Psychiatry, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: Burç Çağrı
authors.initials: BÇ
authors.lastname: Poyraz
authors.affiliation: Department of Psychiatry, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: Cana Aksoy
authors.initials: CA
authors.lastname: Poyraz
authors.affiliation: Department of Psychiatry, Kahramanmaraş State Hospital, Kahramanmaraş, Turkey.
authors.forename: Erol
authors.initials: E
authors.lastname: Bozhüyük
authors.affiliation: Department of Child and Adolescent Psychiatry, Diyarbakır Pediatric Hospital, Diyarbakır, Turkey.
authors.forename: Nurullah
authors.initials: N
authors.lastname: Bolat
authors.affiliation: Department of Psychiatry, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: İbrahim
authors.initials: İ
authors.lastname: Balcioğlu
authors.affiliation: Department of Medical Biology, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: Anıl Çağla
authors.initials: AÇ
authors.lastname: Özkiliç
authors.affiliation: Department of Medical Biology, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: Zehra Seda
authors.initials: ZS
authors.lastname: Genç
authors.affiliation: Department of Medical Biology, University of Istanbul, Cerrahpaşa Medical School, Istanbul, Turkey.
authors.forename: Müjgan
authors.initials: M
authors.lastname: Cengiz
keywords: Cognitive impairment; gene polymorphism; neurological soft signs; schizophrenia; serotonin-2A receptor gene