Document Type : Original Article

Authors

• Shirin Farjadian ¹
• Bahareh Fakhraei ²
• Zahra Niknam ³
• Mahboubeh Nasiri ⁴
• Aslan Azad ⁵
• Mojtaba Farjam ⁶
• Alireza Nikseresht ⁷

¹ Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

² Department of Psychiatry, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

³ Iran Neurological Association, Tehran, Iran

⁴ Allergy Research Center, Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran

⁵ School of Pharmacy, International Branch, Shiraz University of Medical Sciences, Shiraz, Iran

⁶ Noncommunicable Diseases Research Center, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran

⁷ Department of Neurology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

Abstract

Background: Multiple sclerosis (MS) is the most common neuroinflammatory disease in young adults. Anxiety and depression may predispose individuals to MS and flare-ups. Serotonin transmission is modified in some brain regions of patients with MS, and these changes may contribute to their psychiatric abnormalities. We studied the frequencies of common polymorphisms of the serotonin reuptake transporter (SERT) gene in patients with MS according to their psychological status.
Methods: The 5-HTTLPR, rs25531, and STin2VNTR polymorphisms of the SERT gene were genotyped by polymerase chain reaction (PCR)-based methods in 100 patients with MS and 100 healthy controls.
Results: There were no remarkable differences in SERT gene polymorphisms between patients with MS and healthy controls. Unlike the control group, 41% of the patients showed some degree of depression based on Beck Depression Inventory (BDI), but no association was observed between SERT gene polymorphisms after the patients were stratified by depression status.
Conclusion: In addition to SERT gene polymorphisms, modulation of serotonin at the synapses may also be regulated by genetic variations in tryptophan hydroxylase type 2 and serotonin receptors. Further studies with functional brain imaging of the serotonergic system in patients with MS can provide information on the role of serotonin in this disease.