Author Affiliation: Reta Lila Weston Research Laboratories, Department of Molecular Neuroscience, UCL Institute of Neurology, London, England.
The familiality of the major psychiatric disorders, bipolar disease and schizophrenia, has been long recognized and yet, uniquely, the identification of accepted genetic loci has been very difficult. Positional localization of loci in kindreds with apparently mendelian forms of the disease was not confirmed, candidate gene studies did not generally yield reproducible results, and the early, moderately sized, genome-wide association studies did not yield convincing results. This lack of convincing success was in contrast, for example, to the success in neurologic diseases, where not only have many loci been found, but for each disease, they map onto biochemical pathways1,2 and obey rather simple rules as to the predisposing variants found (Table). This has led some, including me,4 to be skeptical of the approaches that have been taken and suggest that the absence of evidence for genetic lesions was gradually becoming the evidence for absence and that to a large extent, familiality must reflect shared environments or experiences.
Hardy J. Psychiatric GeneticsAre We There Yet?. JAMA Psychiatry. 2013;70(6):569-570. doi:10.1001/jamapsychiatry.2013.216