Porphyria Testing & Counseling

Mary, living with a type of porphyria


Alnylam Act TM: Third-Party Genetic Testing and Counseling Programs Offered at No Charge

Alnylam is sponsoring no-charge third-party genetic testing and counseling for individuals who may carry a gene mutation known to be associated with the acute hepatic porphyrias. The Alnylam ActTM program was created to reduce barriers to genetic testing and counseling to help people and their healthcare providers make more informed decisions about their health.


The genetic testing service is available in the United States and Canada and the genetic counseling service is available in the United States. Learn more about what genetic testing and counseling are and how the process works here or by downloading the brochures below.

About the Acute Hepatic Porphyrias

There are four types of acute hepatic porphyrias (AHP): acute intermittent porphyria (AIP), variegate porphyria (VP), hereditary coproporphyria (HCP), and ALAD-deficient porphyria (ADP).


Acute hepatic porphyrias are characterized by acute, potentially life-threatening attacks and chronic debilitating symptoms that negatively impact patients’ quality of life.


Attacks are commonly characterized by severe abdominal pain, vomiting, nausea, rapid heart rate (tachycardia), and constipation. During an attack, a person may also experience muscle weakness or paralysis, seizures, low sodium levels (hyponatremia), and mental changes such as anxiety, confusion, or hallucinations in severe cases.


HCP and VP are classified as acute but can also have symptoms that affect the skin—specifically blistering skin lesions on sun-exposed areas. Skin symptoms can be present with or without attacks.


HCPs: Want more information about this disease to share with patients? Start Here

Genetic testing and counseling may help to:
  • Identify risk of disease for patients and their family members
  • Shorten the time to diagnosis and prevent misdiagnoses
  • Determine if patients are eligible to participate in clinical trials
  • Provide information about support resources such as patient advocacy organizations


Download the Alnyam ActTM Brochures for the Acute Hepatic Porphyrias

For Healthcare Professionals

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For Patients

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Interested in learning about our porphyria studies? Get started here.

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Porphyrias are a group of rare, most often inherited, disorders caused by a defect in the pathway that makes heme in your body.

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