FDA Sources of Rare Disease/Orphan Product Information Rare disease Information Directory from the U.S. Food and Drug Administration
GeneTests National Institutes of Health - Medical genetics information resource, gene reviews, laboratory and clinic directory, educational materials.
Genetic Alliance Coalition of hundreds of genetic advocacy organizations, health professionals, clinics, hospitals and companies
Genetic and Rare Conditions Site Medical information and organizations dealing with rare diseases.  Diseases are listed in alphabetic order.
National Human Genome Research Institute National Institutes of Health Studies aimed at understanding the structure & function of the human genome & its role in health and disease,
National Organization for Rare Disorders Free and subscription based info on rare diseases
National Institutes of Health - Office of Rare Diseases  Research and clinical trials and information, rare disease information, support groups, genetics information.