Author(s)

Nuntika Thavichachart^1*, Taisei Mushiroda², Thongchai Thavichachart³, Ongart Charoensook³, Anchalee Prasansuklab^1,4, Prathan Rutchatajumroon³, Sookjaroen Tangwongchai¹, Puangsoi Worakul¹, Buranee Kanchanatawan¹, Siriluck Suppapitiporn¹, Atapol Sughondhabirom¹, Chutima Roomruangwong¹, Wasun Chantratita⁵, Atsushi Takahashi⁶, Michiaki Kubo⁷, Naoyuki Kamatani⁶, Yusuke Nakamura⁸

¹Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
²Laboratory for Pharmacogenetics, RIKEN Center for Genomic Medicine, Kanagawa, Japan.
³Thailand Center of Excellence for Life Sciences (Public Organization), Ministry of Science and Technology, Bangkok, Thailand.
⁴Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand.
⁵Department of Pathology, Faculty of Medicine, Mahidol University, Bangkok, Thailand.
⁶Laboratory for Statistical Analysis, RIKEN Center for Genomic Medicine, Kanagawa, Japan.
⁷Laboratory for Genotyping Development, RIKEN Center for Genomic Medicine, Kanagawa, Japan.
⁸Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Posttraumatic stress disorder (PTSD) is a psychiatric disorder found in individuals afflicted by a traumatic event. Multiple environmental and genetic factors can contribute to PTSD susceptibility. Since it is rare to find members of the same family afflicted by the same catastrophic event, it is not practical to determine PTSD susceptibility genes by a gene linkage analysis. A natural disaster, such as the 2004 Tsunami, provided us with a rare chance for a genetic analysis of PTSD. To identify SNPs associated with PTSD susceptibility, we conducted a genome-association study (GWAS) in Thai-Tsunami survivors. Initial phase of the study with 396 chronic PTSD patients and 457 controls, we identified top ninety SNPs (P < 1 × 10^-4), which were further assessed in the second phase with 395 chronic PTSD patients and 798 controls. Two SNPs (rs267950 and rs954406), were identified in the second phase, and subjected to fine mapping using a data set from both phases. SNP rs267943 showed the strongest association with PTSD susceptibility and was in complete linkage disequilibrium with SNP rs267950 with P = 6.15 × 10^-8, OR = 1.46 and 95% CI = 1.19 - 1.79, reaching genome-wide significance. SNP rs267943 is located on chromosome 5 in the intron of the death-associated protein 1 (DAP1) gene and, when linked to a synthetic promoter, could regulate transcription. To our knowledge, this is the first GWAS for PTSD susceptibility in an Asian population which could provide an important insight into the genetic contribution of PTSD and may lead to new treatment strategies for PTSD.

Death-Associated Protein 1 Gene (DAP1), Genetics, Genome-Wide Association Study (GWAS), Posttraumatic Stress Disorder (PTSD), Tsunami

Thavichachart, N. , Mushiroda, T. , Thavichachart, T. , Charoensook, O. , Prasansuklab, A. , Rutchatajumroon, P. , Tangwongchai, S. , Worakul, P. , Kanchanatawan, B. , Suppapitiporn, S. , Sughondhabirom, A. , Roomruangwong, C. , Chantratita, W. , Takahashi, A. , Kubo, M. , Kamatani, N. and Nakamura, Y. (2015) Genome-Wide Association Study in Thai Tsunami Survivors Identified Risk Alleles for Posttraumatic Stress Disorder. Open Journal of Genetics, 5, 43-57. doi: 10.4236/ojgen.2015.52004.