This organization provides support and information for individuals suffering from Irritable Bowel Syndrome (IBS), focusing on awareness, symptoms, and management strategies.

北京爱稀客肺动脉高压罕见病关爱中心 is a public organization that provides support and assistance to patients with pulmonary arterial hypertension in China, focusing on improving their quality of life and raising awareness about rare diseases.

The ITP Support Association is a UK charity that supports patients and families affected by Immune Thrombocytopenia (ITP) by providing information, support, and funding for research and medical education.

The Jack Bear Foundation is dedicated to raising awareness and funding research for Spinocerebellar Ataxia Recessive Type 15, a rare degenerative genetic disease.

Jack's Tomorrow is dedicated to funding research for PURA Syndrome, aiming to develop treatments and ultimately a cure for the disease.

The Jain Foundation is dedicated to finding a cure for dysferlinopathy, also known as LGMD2B, LGMDR2, and Miyoshi Myopathy 1, by supporting research, clinical trials, and providing resources for patients and clinicians.

Jamal's Helping Hands is a non-profit organization that provides support and resources to patients and families dealing with chronic illnesses, helping them navigate the healthcare system and improve their quality of life.

The Jansen's Foundation aims to raise awareness and support research for Jansen’s metaphyseal chondrodysplasia, a rare skeletal condition.

The Job Accommodation Network provides expert guidance on workplace accommodations, helping employers manage accommodations for individuals with disabilities.

The Joshua Frase Foundation supports research and provides resources for myotubular myopathy, including an international patient registry and various support services for families affected by the disorder.

The Joubert Syndrome & Related Disorders Foundation supports families affected by Joubert Syndrome by providing resources, emotional support, and opportunities for connection within an international community.

Julia's Wings Foundation supports families of children with life-threatening hematological diseases such as aplastic anemia, MDS, and PNH, while raising awareness and funding medical research.

Breakthrough T1D Canada is dedicated to advancing research and support for individuals living with type 1 diabetes (T1D), aiming to improve daily life and work towards a cure.

KARES Foundation advocates for individuals affected by KDM5C genetic variants, providing research, education, and support to improve their lives.

The KAT6 Foundation supports individuals and families living with KAT6A and KAT6B syndromes by funding research, providing assistive equipment, and raising awareness.

The KCNT1 Epilepsy Foundation supports individuals with KCNT1-related epilepsy by providing educational resources and facilitating research to find a cure for this condition.

Kennedy Krieger Institute provides specialized care and resources for children with brain disorders and injuries, focusing on their development and well-being.

The Kennedy’s Disease Association (KDA) is a non-profit organization dedicated to improving the lives of those affected by Kennedy's Disease, providing resources, support, and funding for research toward a cure.