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Gene polymorphisms and response to transcranial direct current stimulation for auditory verbal hallucinations in schizophrenia

Published online by Cambridge University Press:  21 March 2018

Harleen Chhabra ,
Venkataram Shivakumar ,
Manjula Subbanna ,
Sunil V. Kalmady ,
Anushree Bose ,
Sri Mahavir Agarwal ,
Vanteemar S. Sreeraj Open the ORCID record for Vanteemar S. Sreeraj [Opens in a new window] ,
Damodharan Dinakaran ,
Janardhanan C. Narayanaswamy  and
Monojit Debnath
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Harleen Chhabra
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Venkataram Shivakumar
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Manjula Subbanna
Affiliation:
Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Department of Human Genetics, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Sunil V. Kalmady
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Anushree Bose
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Sri Mahavir Agarwal
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Vanteemar S. Sreeraj
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Damodharan Dinakaran
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Janardhanan C. Narayanaswamy
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Monojit Debnath
Affiliation:
Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Department of Human Genetics, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
Ganesan Venkatasubramanian*
Affiliation:
WISER Program, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
*
Author for correspondence: Dr. Ganesan Venkatasubramanian, Professor of Psychiatry, Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore 560029, India. Tel: 00 91 80 26995256; E-mail: venkat.nimhans@gmail.com
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Abstract

Objective

Recent observations demonstrate a significant ameliorative effect of add-on transcranial direct current stimulation (tDCS) on auditory verbal hallucinations (AVHs) in schizophrenia. Of the many SNPs, NRG1 rs35753505 and catechol-o-methyl transferase (COMT) rs4680 polymorphisms have shown to have a strong association with neuroplasticity effect in schizophrenia.

Methods

Schizophrenia patients (n=32) with treatment resistant auditory hallucinations were administered with an add-on tDCS. The COMT (rs4680) and NRG1 (rs35753505) genotypes were determined. The COMT genotypes were categorised into Val group (GG; n=15) and Met group (GG/AG; n=17) and NRG1 genotypes were categorised into AA group (n=12) and AG/GG group (n=20).

Results

The reduction in auditory hallucination sub-scale score was significantly affected by COMT-GG genotype [Time×COMT interaction: F(1,28)=10.55, p=0.003, ɳ2=0.27]. Further, COMT-GG effect was epistatically influenced by the co-occurrence of NRG1-AA genotype [Time×COMT×NRG1 interaction: F(1,28)=8.09, p=0.008, ɳ2=0.22]. Irrespective of genotype, females showed better tDCS response than males [Time×Sex interaction: F(1,21)=4.67, p=0.04, ɳ2=0.18].

Conclusion

COMT-GG and NRG1-AA genotypes aid the tDCS-induced improvement in AVHs in schizophrenia patients. Our preliminary observations need replication and further systematic research to understand the neuroplastic gene determinants that modulate the effect of tDCS.

Keywords

hallucinationsgenesschizophreniatDCS

Information

Type
Original Article
Information
Acta Neuropsychiatrica , Volume 30 , Issue 4 , August 2018 , pp. 218 - 225
Copyright
© Scandinavian College of Neuropsychopharmacology 2018 

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