PRDM13 and North Carolina macular dystrophy: It is an autosomal dominant condition with complete penetrance but highly variable expressivity (Figure 9) with the gene macular-dystrophy-retinal-1 (MCDR1) on the 6q chromosome. Manes et al. described a novel duplication of PR/SET-domain-13 (PRMD13) causing NCMD, supporting even further the genetic linkage of duplications on the entire sequence of cyclin-c (CCNC) and PRDM13 genes with this degeneration.