Peroxisome Biogenesis Disorder 4a, also known as pbd4a, is related to peroxisome biogenesis disorder 4b and cone-rod dystrophy 2. An important gene associated with Peroxisome Biogenesis Disorder 4a is PEX6 (Peroxisomal Biogenesis Factor 6). Affiliated tissues include liver and eye, and related phenotypes are hepatomegaly and depressed nasal bridge