Facts About Rare Diseases

The linked post discusses whether it is better to spend money on treating rare diseases or using genetic screening (pre-conception and post-conception, potentially linked with fertility treatments related screening) to address them. But a predicate to that debating that intelligently is understanding the underlying problem.

Rare diseases cost Americans around 8 trillion dollars a year. About half of that is direct medical costs. If families are lucky, they may go bankrupt paying for treatment of often questionable effectiveness. The unlucky families may go bankrupt just trying to find a cure; unfortunately less relevant as only about 5% of rare diseases have treatments. . . .

In the United States, a rare disease is defined as one that affects fewer than 200,000 Americans. Despite each disease affecting no more than .06% of the population, there are about 7,000 different rare diseases, meaning roughly 10% of the U.S. population has a rare disease.

These numbers may seem large, but it makes sense if you consider the complexity of human genetics and development. Humans have around 20,000 genes. Mutations in some genes are lethal. Mutations in some genes lead to normal human variation; you may not even know the person has a mutation. And mutations in others lead to rare diseases; not lethal at or before birth, but often quite deleterious. Around 80% of rare diseases are genetic and many of these diseases are discovered in children – the mutations are severe enough to be noticed early.

30% of children with rare diseases do not live past the age of 10. The devastation of rare diseases stems from their chronic, progressive nature and the fact that many involve multi-organ system failure or neurological impairments.

From here.

The average rare disease in the U.S. affects about 4,760 people.

Part of the economic issue is that curing a rare disease generally has a cost comparable to curing a non-rare disease, but benefits fewer people. Yet, a single medical grade genetic test can screen for all genetic diseases.