Letters to the Editor
Obsessive–compulsive disorder associated with sickle β-thalassemia: A genetic link?
Article first published online: 16 OCT 2012
© 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology
Psychiatry and Clinical Neurosciences
Volume 66, Issue 6, page 537, October 2012
How to Cite
Saraf, G., Viswanath, B., Narayanaswamy, J. C., Math, S. B. and Reddy, Y. J. (2012), Obsessive–compulsive disorder associated with sickle β-thalassemia: A genetic link?. Psychiatry and Clinical Neurosciences, 66: 537. doi: 10.1111/j.1440-1819.2012.02382.x
- Issue published online: 16 OCT 2012
- Article first published online: 16 OCT 2012
- Received 26 March 2012; revised 27 June 2012; accepted 3 July 2012.
OBSESSIVE–COMPULSIVE DISORDER (OCD) is a common mental illness with 2–3% lifetime prevalence. OCD has a strong genetic basis, but specific genes have not been identified.1β-Thalassemia and sickle cell anemia (SCA) are rare monogenic hereditary disorders caused by mutations in the β-globin gene located on 11p15.5. Sickle β-thalassemia (SBT) is a compound heterozygous form of the disorder with both mutations.2 We report a rare case of familial OCD with SBT. The patient gave informed consent to publish this report.
An 18-year-old south Indian man presented with 4-year illness characterized by obsessions of symmetry, need for perfection with repeating, ordering, blinking and staring compulsions. He was diagnosed as having OCD according to DSM-IV criteria. He had a family history of tic disorder (TD) in his father and OCD in a male second-degree relative. At the age of 6 he was diagnosed with SBT, for which he had received approximately 400 blood transfusions till date. Hemoglobin (Hb) variant analysis (HbF-33.6, HbA2-5.5 and HbS-57.8) and molecular testing (compound heterozygous for codon 15 (G A) and codon 6 (A T) mutation in β-globin gene) confirmed SBT. His father was heterozygous for HbS (HbF-1.3, HbA2-3.2 and HbS-57.8) at codon 6 (A T). His mother was heterozygous for β-thalassemia (HbF-2.1, HbA2-5.2 and HbS-0) at codon 15(G A). They were both asymptomatic. He went into remission on escitalopram 30 mg and clomipramine 100 mg over a period of 3 years follow-up.
To the best of our knowledge, this is the first report of OCD comorbid with SBT. In addition, there was a family history of OCD and TD in this particular case. In a recent study that examined psychiatric comorbidity in a group of children with β-thalassemia, OCD was found in 15% of the sample.3 One study in young adults with β-thalassemia found personality characterized by OC traits, somatization and depression.4 There are no reports of comorbidity between SCA and OCD.
β-Thalassemia and SCA are caused by specific mutations in the β-globin gene located at 11p15.5.2 Familial clustering of OC spectrum disorders (OCD and TD) and β-globin gene-related disorders in the present patient's family suggests a possible genetic link. Two putative candidate genes for OCD (DRD4 and BDNF) are located at 11p15.5.1 This area has also been implicated in the OCD Collaborative Genetics Study linkage analysis.5