Reality TV star Rob Kardashian made Hollywood headlines in May when he admitted to having obsessive compulsive disorder (OCD). The baby brother of Kim, Kourtney, and Khloe Kardashain has a fixation with the number seven and other obsessions, as viewers of E!’s “Khloe & Lamar” know.
Researchers have yet to find the gene responsible for OCD, but have found some genetic clues for future study following the first genome-wide association study (GWAS) for the disorder, results for which were published online today in the journal Molecular Psychiatry.
In a multi-institutional study, researchers discovered a possible association between OCD and the gene BTBD3, which is within DLGAP1, a close relative of a gene that has produced OCD-like symptoms in mice when deleted.
The International OCD Foundation Genetic Collaborative—consisting of more than 20 research groups in nine countries—analyzed almost 480,000 single-nucleotide polymorphisms (SNPs) in 1,465 individuals with OCD, more than 5,500 controls and from 400 trio samples consisting of an OCD patient and both parents.
While no SNPs were identified as being associated with OCD at a GWAS-significant level, researchers said they saw “a significant enrichment” of methylation-quantitative trait loci (QTL) and frontal lobe QTLs that regulate expression levels of messenger RNAs or proteins was observed within the top-ranked SNPs, “suggesting these top signals may have a broad role in gene expression in the brain, and possibly in the etiology of OCD.”
The OCD study was led by Evelyn Stewart, M.D., then of Massachusetts General Hospital (MGH)’s Psychiatric and Neurodevelopmental Genetics Unit (PNGU), and now based at the University of British Columbia, and David Pauls, Ph.D., who remains at MGH-PNGU.
BTBD3 is closely related to a gene that may be involved in Tourette Syndrome, the subject of a separate GWAS study involving many of the same researchers also published today.