Chromosome 12

PXR1. Peroxisomes are not detected in Zellweger syndrome fibroblasts (A) but can be reconstituted by transfection with PXR1 gene (B) IMAGE CREDIT: Nancy Braverman, Gabrielle Dodt, Hugo Moser, Stephen Gould and David Valle from the Johns Hopkins University, Baltimore, MD, USA. PAH. Millions of newborns per year are screened for deficiency of phenylalanine hydroxylase to identify those susceptible to phenylketonuria (PKU)