Syntenic clusters of genes with a common purpose have been described previously [23,24,25,26,27,28] and include integrons in bacteria [25], a block contributing to cardiomyopathy in humans [28], and the NTAD cluster (NCAM1-TTC12-ANKK1-DRD2 [30]), mentioned above as part of this study. This evidence concerns the gene DRD2 and cardiomyopathy.