While pancreatitis can occur as a result of medications, infections, trauma, autoimmune disease or lifestyle factors, pancreatitis can also happen as a result of genetics. The symptoms of hereditary pancreatitis are similar to other forms of pancreatitis and may include abdominal pain, nausea and vomiting.
Here, we’ll take a look at what happens in hereditary pancreatitis and why and how genetic testing for diseases could impact its treatment.
What Happens in Hereditary Pancreatitis?
Hereditary pancreatitis is a genetic condition that’s characterized by recurrent episodes of inflammation of the pancreas that often progresses to chronic pancreatitis in early adulthood. Unlike most other forms of pancreatitis, patients with hereditary pancreatitis usually start to experience symptoms of acute pancreatitis in childhood. These episodes can be characterized by an acute attack of abdominal pain, nausea, fever or vomiting. Clinically, hereditary pancreatitis is defined as (1) recurrent acute or chronic pancreatitis in ≥2 individuals in ≥2 generations of a family or (2) pancreatitis in an individual with a known disease-causing variant in the PRSS1 gene.
According to the U.S. National Library of Medicine, the persistent inflammation damages the pancreas and reduces function. Individuals with hereditary pancreatitis have an increased risk to develop pancreatic cancer, which is believed to be from prolonged inflammation in the pancreas. The National Pancreas Foundation reports that patients with hereditary pancreatitis have a 40% lifetime risk of developing pancreatic cancer, though estimates in the literature range from 7.2% to 40% at age 70 years.
What Causes Hereditary Pancreatitis?
Variants in the PRSS1 gene are the primary cause of hereditary pancreatitis. However, not all families with hereditary pancreatitis have an identifiable genetic cause in the PRSS1 gene. It’s estimated that between 60% to 85% of people with hereditary pancreatitis have an identifiable genetic cause. Variants in other genes, some of which are not yet identified, can cause hereditary pancreatitis in those who do not have a disease-causing variant in PRSS1.
The PRSS1 genes give instructions for making the enzyme cationic trypsinogen, which is produced in the pancreas and aids in the digestion of food.
The U.S. National Library of Medicine explains: “Some PRSS1 gene mutations that cause hereditary pancreatitis result in the production of a cationic trypsinogen enzyme that is prematurely converted to trypsin while it is still in the pancreas. Other mutations prevent trypsin from being broken down. These changes result in elevated levels of trypsin in the pancreas. Trypsin activity in the pancreas can damage pancreatic tissue and can also trigger an immune response, causing inflammation in the pancreas.”
For reasons that remain unknown, not all individuals with a disease-causing variant in PRSS1 develop hereditary pancreatitis. The chance of developing pancreatitis due to a variant in the PRSS1 gene has been estimated to be approximately 80%.
How Genetic Testing for Diseases Can Impact Treatment
Genetic testing involves examining your genes for changes that may or may not cause illness or disease. The results of a genetic test allow your doctors to make better targeted treatment decisions for your disease.