Association between a genetic variant in the serotonin transporter gene (SLC6A4) and suicidal behavior in patients with schizophrenia

Patients diagnosed with schizophrenia from three Scandinavian samples were assessed for presence or absence of suicide attempts, based on record reviews and interview data. Seven SLC6A4 single nucleotide polymorphisms (SNPs) were genotyped in 837 schizophrenia patients and 1,473 control individuals. Association analyses and statistical evaluations were performed with the program UNPHASED (version 3.0.9).We observed an allele association between the SNP rs16965628, located in intron one of SLC6A4, and attempted suicide (adjusted p-value 0.01), among patients with schizophrenia. No association was found to a diagnosis of schizophrenia, when patients were compared to healthy control individuals.The gene SLC6A4 appears to be involved in suicidal ideation among patients with schizophrenia. Independent replication is needed before more firm conclusions can be drawn.