Functional -1149 g/t polymorphism of the prolactin gene in schizophrenia.

Background: Prolactin in schizophrenia is considered in the context of antipsychotic drug-induced hyperprolactinemia. However, the European First Episode Schizophrenia Trial showed that hyperprolacti nemia occurred in a significant proportion of drug-naïve first-episode schizophrenia patients, which shows that it may also be caused by other factors, including genetic predisposition. Therefore, we investigated the functional polymorphism of the prolactin gene in schizophrenic patients compared with control subjects.
Method: The experimental group consisted of 403 patients with schizophrenia: 202 females and 201 males. The control group consisted of 653 subjects: 377 females and 276 males. The functional polymorphism -1149 G/T (rs1341239) of the prolactin gene was genotyped using the TaqMan single-nucleotide polymorphism allelic discrimination method.
Results: The distribution of genotypes in schizophrenic patients was significantly different from those of the control subjects (p=0.031). After breaking down by gender, for male patients, the difference versus control males was significant for both genotypes and alleles (p=0.031 and p=0.002, respectively), with allele G being observed more frequently in schizophrenic patients.
Conclusion: The results may suggest a possible abnormality of the functional -1149 G/T polymorphism of the prolactin gene in schizophrenia, especially in male patients, similar to that found in autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. This could also correspond with an autoimmune pathogenesis of schizophrenia.
(Copyright © 2011 S. Karger AG, Basel.)