For psychiatric disorders, such as autism, schizophrenia and bipolar disorder, genetic architectures have proven to be complex, spawning a lively debate as to the nature of this complexity (Klein et al., 2010; McClellan and King, 2010). This debate has focused on the relative merits of two contrasting (but conceptually-related) hypotheses: the common variant common disease (CVCD) and rare variant common disease (RVCD) models.
