Improving Health

Genetic Diseases

Sickle Cell Disease

In the early 1970s, most Americans with sickle cell disease (SCD) died in childhood. Today, thanks in part to NIH-supported research to understand the basis of SCD and develop effective interventions, the more than 100,000 individuals in the U.S. with SCD are living into their forties or fifties, and beyond.

Image credit: National Center for Advancing Translational Sciences, NIH

  • SCD is characterized by the buildup of an abnormal protein in red blood cells causing pain, fatigue, and damage throughout the body.
  • NIH-funded research in the late 1940s helped discover how SCD is inherited and led to universal newborn screening for SCD.
  • In 1998, hydroxyurea became the first drug approved for treating adults with SCD; in 2017, it was approved for pediatric patients.
  • Blood and bone marrow transplants are the only cure for SCD, with a 90% cure rate in patients with a healthy immune-matched donor.

Neurofibromatosis Type 1

More than 30 years of NIH-supported research led to the 2020 FDA approval of selumetinib, the first effective treatment for children with neurofibromatosis type 1 (NF1) and associated tumors. In clinical trials, this treatment caused tumors to shrink in 70% of trial participants.

Image credit: Daniel Soñé/NCI

  • NF1 is a genetic disorder that affects approximately 1 in 3,000 people. The disease can lead to the development of disfiguring, disabling, and painful benign and malignant tumors, called plexiform neurofibromas (PNs).      
  • Selumetinib is now the first effective treatment for children with PNs that can't be removed by surgery. Prior to the approval of selumitinib, there were no effective treatment options for inoperable tumors.

Cystic Fibrosis

In the 1980s, most people with cystic fibrosis (CF) died as teenagers. Thanks to NIH-funded research—including identification of the gene responsible for the disorder and subsequent development of therapies—people with CF are living into middle age and beyond, with hope for a cure on the horizon.

Image credit: Megan Murray, Hazel’s Roots Photography

  • CF is an inherited disorder that causes problems with breathing and digestion, and it affects about 35,000 people in the U.S. 
  • CF results from mutations in the CFTR gene. These gene mutations were identified in 1989 through a collaborative effort co-led by former NIH Director, Francis Collins.
  • In 2019, FDA approved a combination therapy of three drugs that restores the function of the CFTR protein in people with the most common CFTR mutation, which is about 90% of people with CF.


Sickle Cell Disease

  1. What Is Sickle Cell Disease?:
  2. Building on Our Legacy of Excellence in Sickle Cell Disease Research:
  3. Hydroxyurea use in sickle cell disease:
  4. Hydroxyurea for the Treatment of Patients With Sickle Cell Anemia:
  5. Article: FDA approves hydroxyurea for treatment of pediatric patients with sickle cell anemia:

Neurofibromatosis Type 1

  1. Article: Selumetinib: The First Effective Treatment for Plexiform Neurofibromas:

Cystic Fibrosis

  1. Article: Dare to Dream: The Long Road to Targeted Therapies for Cystic Fibrosis:
  2. Collins FS. N Engl J Med. 2019;381(19):1863-1865. PMID: 31670919.
  3. Cystic Fibrosis:

This page last reviewed on March 1, 2023