Within the three most-replicated dyslexia loci, four candidate genes for dyslexia have been identified: DYX1C1 in DYX1 on chromosome 15q21 (Taipale et al., 2003b), DCDC2 (Meng et al., 2005b) and KIAA0319 (Cope et al., 2005a) in DYX2 on chromosome 6p21, and ROBO1 in DYX5 on chromosome 3p12–q12 (Hannula-Jouppi et al., 2005). This evidence concerns the gene DCDC2 and dyslexia.