The remaining genes, such as GLYCTK (Sass et al., 2010), DRD5 (Daly et al., 1999), NPHP3 (Bergmann et al., 2008), and FANCI (Mehta and Tolar, 1993), were well-characterized pathogenic genes for some other rare diseases with recessive mode of inheritance or multi-gene diseases, such as D-glyceric aciduria, attention deficit-hyperactivity disorder, Meckel syndrome, and Fanconi Anemia. This evidence concerns the gene DRD5 and attention deficit-hyperactivity disorder.