Fig. 2.

Schematic representation of the MECP2 telomeric region. (Top) Blue boxes represent the pathogenic rearrangements documented in the literature thus far: distal breakpoint grouping of most of the patients with MECP2 duplications, deletions and/or gene conversions of the Opsin genes that cause color blindness, and deletions of the EMD gene that cause Emery–Dreifuss muscular dystrophy (EDMD). (Middle) The genomic context telomeric to MECP2. LCRJ spans 114 kb and is formed by three genes and/or pseudogenes that constitute the Opsin array, OPN1LW, OPN1MW, and TEX28. The nearby LCRs, K1 and K2, are positioned in inverted orientation, have 99% sequence identity, and are 11.3 kb in length. Hatched bars within arrows inside the LCRs K represent the small region that is 100% identical between them. Blue arrows show alignment of the join points of the patients carrying complex rearrangements (triplications embedded in duplications). (Bottom) Human structural variation (yellow rectangles) includes CNVs and inversions; evolutionary genomic rearrangements (orange rectangles) include the duplication of the Opsin gene and further acquisition of the trichromatic color vision during the primate evolution in addition to a recurrent inversion that has been occurring multiple times in eutherians. *, based on data reported in Carvalho et al. (56).