Methylmalonic acidemia with homocystinuria
Synonyms: Combined defect in adenosylcobalamin and methylcobalamin synthesis | Methylmalonic aciduria with homocystinuria
A rare inborn error of vitamin B12 (cobalamin) metabolism characterized by megaloblastic anemia lethargy failure to thrive developmental delay intellectual deficit and seizures. There are four complementation classes of cobalamin defects (cblC cblD cblF and cblJ) that are responsible for methylmalonic acidemia – homocystinuria (methylmalonic acidemia – homocystinuria cblC cblD cblF and cblJ).
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview.
Reference: Access aggregated data from Orphanet at Orphadata.
Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http: //www.orphadata.org. Data version June 2023.
Newly diagnosed with
Methylmalonic acidemia with homocystinuria?
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Advocacy Organizations
HCU Network America
HCU Network America strives to inform and provide resources for patients and families, create connections, influence state and federal policy, and support the advancement of diagnosis and treatment for HCU and related disorders.
Canadian PKU and Allied Disorders (CanPKU)
To help those who live with rare diseases that are manage by a restricted protein medical diet bringing education, awareness and advocacy to the community
Organic Acidemia Association
Our mission is to empower families and health care professionals with knowledge in these disorders. We support early intervention through expanded newborn screening, solicit contributions, and distribute funding that supports research toward improved treatment, and eventual cures in the areas of Organic Acid disorders.
Mississippi Metabolics Foundation
Mississippi Metabolics Foundation (MMF) was founded to raise awareness, educate, and provide support to those living or caring for someone with genetic metabolic disorders/inborn errors of metabolism (IEM).
Louisiana Metabolic Disorders Coalition
We support, educate, and advocate for patients & families affected by metabolic disorders.
Care-for-Rare America Inc
To establish a global alliance in order to identify the genetic causes of rare diseases and develop effective treatments, following a three-stage approach: recognize, understand, cure.
Syndromes Without A Name (SWAN) Australia
Provide information, support and advocacy to families caring for a child with an undiagnosed or rare genetic condition.
Center for Chronic Illness
The Center for Chronic Illness (CCI) promotes well-being and decreases isolation for those impacted by ongoing health challenges through support and education.
Inclusive Skating
TO INCLUDE, INFORM AND INSPIRE people around the globe through the joy of skating, reflecting the compassion, respect and innovation that make ours the world’s premier inclusive organisation. Inclusive Skating is dedicated to the advancement of public participation in sport and the promotion of equality and diversity. Our primary objective is the development and implementation of programming which fosters the inclusion of skaters with any form of impairment or disability. Our ethos of inclusion extends to skaters of all ages and backgrounds; we welcome all with open arms. Values of empathy, integrity and empowerment are central to the pursuit of these goals. We believe that everyone should have the opportunity to experience the community, camaraderie, self-fulfilment, achievement, challenge, and thrill that participation in skating sports offers. We work to create these opportunities by offering activities, educational resources, events, training, and championships for our community.
Rare Disease Ghana Initiative
To improve the wellbeing and quality of life of persons living with undiagnosed and rare diseases in Ghana
Our Odyssey Inc.
Connecting young adults impacted by a rare or chronic condition with social and emotional support in the hope of improving their quality of life.
Jamal’s Helping Hands
Jamal's Helping Hands provides services for patients affected by rare disease and their families. With a vision to become a premier resource and national leader in education, outreach, advocacy, and support to individuals affected by rare disease. JHH enhances the quality of its clients lives by providing an array of services to make the experience of rare disease easier.
Patient Advocate Foundation
Patient Advocate Foundation (PAF), founded in 1996, is the nation’s leading direct patient services organization whose mission is to safeguard patients with chronic, life-threatening, and debilitating diseases through effective mediation of issues related to access to care and preservation of financial stability. Patients must be seeking help with any of the following needs related to their diagnosis: • Accessing prescribed healthcare, including understanding their healthcare benefits • Issues related to their health insurance benefits, including denials of care, out-of-pocket costs, network issues, and insurance options • Financial concerns, including cost-of-living expenses and medical expenses • Practical needs, including transportation and nutritional needs • Assistance with filing an application for disability Since its inception, PAF has provided direct, sustained patient assistance to more than 1.7 million patients and touched many more through its website and outreach events. Amongst the more common issues that patients and caregivers call PAF for help with include the inability to afford transportation expenses, inability to afford rent/mortgage, inability to afford their co-pay for medications, and inability to afford utilities and resulting shut-off notices. PAF serves patients with numerous health conditions, the majority of which have some form of cancer. Non-cancer diagnoses included rare diseases, chronic and debilitating conditions, nervous system conditions, cardiovascular conditions and vascular disease, autoimmune diseases, and diabetes. PAF solicits and receives donations to its programs from a multitude of sources including government agencies, non-profit organizations and for-profit organizations in the healthcare sector, including pharmaceutical manufacturers and healthcare providers. Patient Advocate Foundation also has several distinct programs targeting specific populations with an emphasis on the underserved.
Botswana Organisation for rare Diseases
advocate for Rare disease patients and their families
Rare Disorders Kenya
Provide a strong common voice to advocate for a rare disease health policy and a better healthcare system that works for those with rare diseases
Youth and Women for Opportunities Uganda-YWOU
Youth and Women for Opportunities-YWOU an organization that we represent is patient organization re-presentative, patient and institution and individual capacity builder supporting PLWRD’s to obtain diagnosis, treatment and drugs for those suffering consequences of being undiagnosed or misdiagnosed and lack treatment and those who lack precise diagnosis for rare, orphan and undiagnosed diseases preventing PLWRD’s accessing the most adapted care, treatment or surgery, have delayed access to the most appropriate care, treatment or surgery
Indo US Organization for Rare Diseases (IndoUSrare)
With an initial focus on the Indian diaspora, our mission is to build cross-border collaborations to connect stakeholders of rare diseases in low- and middle-income regions—such as India—with their counterparts & clinical researchers in the US. This allows to improve the diversity of clinical trial participants, accelerates RnD, & improves equitable access to life-saving therapies.
Clinical Trials
For a list of clinical trials in this disease area, please click here.