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A rare disease is a condition that affects fewer than 200,000 people nationwide. Some of them affect fewer than 100 people. There are close to 7,000 rare diseases, many of which are caused by defective genes. Most rare diseases are fatal.
Some rare diseases include:
Amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease. In ALS, the nerve cells that send messages to your voluntary muscles — the ones you can control, like in your arms and legs — die. At first, this causes mild muscle problems. You may have trouble walking, writing, or speaking. In time, you lose your strength and cannot move. When muscles in your chest fail, you cannot breathe.
Fabry disease. In Fabry disease, fat-like substances build up in the eyes, kidneys, and blood vessels. People with Fabry disease often survive into adulthood but are at increased risk of heart attack, stroke, and kidney failure.
Cervical dystonia. This is a painful condition in which your neck muscles contract (shorten) on their own, causing your head to twist or turn to one side.
Getting a diagnosis for a rare disease can be frustrating and take a long time. If you have a rare disease, it can be difficult to find a specialist who knows about your disease. You might need to travel to see a specialist. If treatments exist, they often cost a lot because only a few people use them. Finding others who can relate to your experience can be hard. Online support groups can help people affected by rare diseases connect no matter where they live.
Altogether, rare diseases affect as many as 25 million Americans. Learning about rare diseases and finding treatments for them are an important public health concern.
Explore other publications and websites
Financial Assistance Information — This document provides resources that may help in finding information on financial aid for medical treatment.
Genetic and Rare Conditions Site (Copyright © University of Kansas Medical Center) — This website provides information about many genetic and rare conditions. It also links to teaching activities for educators about some of the conditions.
Genetics Home Reference — This website provides information on specific genetic conditions and the genes or chromosomes responsible for these conditions.
NORD’s Patient Assistance Programs (Copyright © National Organization for Rare Disorders) — The National Organization for Rare Disorders offers programs to assist uninsured or under-insured individuals with rare disorders. this web page lists the programs that NORD currently offers.
Rare Diseases Terms — This Internet site provides a list of terms associated with various rare diseases.
Connect with other organizations
Genetic Alliance, Inc.
National Human Genome Research Institute, NIH, HHS
National Organization for Rare Disorders
Office of Rare Diseases Research, OD, NIH, HHS
Rare Diseases Clinical Research Network
Content last updated September 22, 2009.
Resources last updated September 22, 2009.
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