Análisis del polimorfismo rs1051730 de CHRNA3 en pacientes con patología dual en población mexicana / Analysis of polymorphism rs1051730 of CHRNA3 in patients with dual pathology in a Mexican population

Introducción: Estudios epidemiológicos han descrito una alta comorbilidad de los trastornos de uso de sustancias con otro trastorno psiquiátrico, al cual se le ha llamado patología dual. Sin embargo, los mecanismos etiológicos de esta asociación continúan siendo difíciles de entender. Objetivo: Realizar un estudio preliminar del efecto del polimorfismo rs1051730 del grupo de genes CHRNA5-CHRNA3-CHRNB4 a través de un estudio de casos y controles. Sujetos y métodos. Se seleccionó a un total de 225 sujetos, divididos en tres grupos: con diagnóstico de trastorno bipolar, con dependencia a la nicotina y sujetos sin dependencia a la nicotina o cualquier otro trastorno psiquiátrico. La genotipificación se realizó mediante reacción en cadena de la polimerasa en tiempo real. El análisis de asociación genética se realizó mediante pruebas de chi cuadrado y regresiones logísticas multivariables. Resultados: Al comparar las frecuencias alélicas con el grupo control, encontramos que el polimorfismo rs1051730 se asoció con el grupo de dependencia a la nicotina (p = 0,03), pero no con el de trastorno bipolar (p = 0,94). Conclusión: La variante rs1051730 se asoció con dependencia a la nicotina en la población mexicana y mostró el mismo efecto en la patología dual. Sin embargo, se recomiendan estudios adicionales para tener resultados concluyentes

Introduction: Epidemiological studies have described a high comorbidity of substance use disorders with another psychiatric disorder, which has been called dual pathology. However, the aetiological mechanisms underlying this association are still not fully understood. Aim: To carry out a preliminary study of the effect of polymorphism rs1051730 of the gene group CHRNA5-CHRNA3-CHRNB4 through a case-control study. Subjects and methods. A total of 225 subjects were selected and divided into three groups: those diagnosed with bipolar disorder, those with nicotine dependence, and subjects without nicotine dependence or any other psychiatric disorder. Genotyping was performed by real-time polymerase chain reaction. Genetic association analysis was performed using chisquare tests and multivariate logistic regressions. Results: On comparing allelic frequencies with the control group, we found that polymorphism rs1051730 was associated with nicotine dependence (p = 0.03), but not with bipolar disorder (p = 0.94). Conclusion: Variant rs1051730 was associated with nicotine dependence in the Mexican population and showed the same effect in dual pathology. However, further studies are recommended to obtain conclusive results

The Thalamostriatal Projections Contribute to the Initiation and Execution of a Sequence of Movements.

One of the main inputs driving striatal activity is the thalamostriatal projection. While the hypothesis postulating that the different thalamostriatal projections contribute differentially to shape the functions of the striatum is largely accepted, existing technical limitations have hampered efforts to prove it. Here, through the use of electrophysiological recordings of antidromically photo-identified thalamostriatal neurons and the optogenetic inhibition of thalamostriatal terminals, we identify that the thalamostriatal projections from the parafascicular and the ventroposterior regions of the thalamus contribute to the smooth initiation and the appropriate execution of a sequence of movements. Our results support a model in which both thalamostriatal projections have specific contributions to the initiation and execution of sequences, highlighting the specific contribution of the ventroposterior thalamostriatal connection for the repetition of actions.