CACNA1D and schizophrenia: In contrast, with regard to the report by Merikanto et al. [14] on an association of slow spindle parameters with a genetic risk score specific for the CACNA1I gene, a schizophrenia risk gene coding for the voltage-gated calcium channel subunit alpha 1 known to be implicated in spindle generation [50–52], in a sample of 150 healthy adolescents [14], we did not replicate this result in our explorative analysis in 150 adults.