Correlation Study Between Dopamine D1 Receptor Gene-48A/G Polymorphism And Schizophrenia

Objective: To investigate the relationship between Dopamine D1 receptor Gene -48A/G polymorphism and schizophrenia in Chinese Han population of Hubei province.Methods: 103 schizophrenia diagnosed according to CCMD-â…¢ R criteria, 188 normal controls were recruited in the study. The Polymerase Chain Reaction-Restriction Fragment Fength Polymorphisms (PCR-RFLP) technique was used to detect the genotypes of the Dl receptor gene in 103 patients and 188 normal controls. 103 patients were administered the neuropsychological tests including Wiscosin Card Sorting Test (WCST) and Wechsler Adult Intelligence Scale-RC (WAIS-RC). 10 indices of above-mentioned tests were written down: Categories achievment, Total errors, Perseverative responses, Perseverative errors, Nonperseverative errors, Arithmetic, Digital Span (obverse recitee), Digital Span (reverse recite), Digital Symbol, Block Design. At the same time, a clinical evaluation of 103 patients was accomplished by The Positive And Negative Syndrome Scales (PANSS).Results: 1) Significant Dopamine Dl receptor gene polymorphism difference was found between Chinese Han population of Hubei province and other nations, such as Caucasians of Unitied Kingdom, Germans and Japanese. 2) Regarding Dopamine Dl receptor gene polymorphisms no statistically significant difference was found between schizophrenic patients and control subjects. The same results also appears in the sex different groups. 3) However, there is significant difference between schizophrenic patients with family history positive and controls( x~2=6.081, p<0.05, OR=0.248, 95% CI=0.082~0.752). 4) No statistically significant difference was found between genotypes and Categories achievment, Total errors, Perseverative responses, Nonperseverative errors, Arithmetic, Digital Span (obverse recite), Digital Symbol and Block Design. But a significant difference was found between genotypes and Perseverative errors and Digital Span (reverse recite). 5) No statistically significant difference was found between the genotypes and the score of the Positive And Negative Syndrome Scale.Conclusion: 1) There was significant Dopamine D1 receptor gene polymorphism difference between Chinese Han population of Hubei province and other nations. 2) No statistically significant overall associations between the Dopamine D1 receptor genetypes and risk of schizophrenia were observed. However, there is significantdifference between schizophrenic patients with family history positive and controls. G allel was possible one of Protection factors for schizophrenia. 3) The Dopamine Dl receptor gene polymorphism was associated with Perseverative errors and Digital Span(reverse recite) tests performance. The found suggest that the The Dopamine Dl receptor gene polymorphism affect working memory and the physiology of the prefrontal cortex in schizophrenic patients, probably by affecting prefrontal dopamine signaling. 5) The The Dopamine Dl receptor gene polymorphism did not affect the syndrome of schizophrenia.