The URLs for data presented herein are as follows:
Cystic Fibrosis Mutation Database, http://www.genet.sickkids.on.ca/cftr/app
Entrez, http://www.ncbi.nlm.nih.gov/entrez/
GeneTests, http://www.genetests.org/
HUGO, http://www.gene.ucl.ac.uk/nomenclature/
Human Gene Mutation Database, http://www.hgmd.cf.ac.uk
Human Genome Variation Society, http://www.genomic.unimelb.edu.au/mdi/dblist/glsdb.html
Mouse Genome Informatics, http://www.informatics.jax.org/ (for the Mouse Genome Database)
Online Mendelian Inheritance in Animals (OMIA), http://omia.angis.org.au/
Online Mendelian Inheritance in Man (OMIM), http://www.ncbi.nlm.nih.gov/Omim/
PAHdb, http://www.pahdb.mcgill.ca/