December 8, 2021

Is Ulcerative Colitis Genetic

Ulcerative Colitis has the highest prevalence in North American and Northern Europe
Tomohiro Takano

Is Ulcerative Colitis Genetic?

Ulcerative colitis (UC) is a form of chronic digestive disease. This condition is characterized by irregular inflammation of the inner surface of the colon and rectum. Patients most often experience bloody diarrhea and abdominal pain. Anemia, fever, and weight may also occur. 

The symptoms of ulcerative colitis tend to appear slowly before becoming more severe. The cause of UC is unknown, but most experts suspect it is a combination of genetic, immune response, and environmental factors.

The Link Between Ulcerative Colitis and Your DNA

The question “Is ulcerative colitis genetic” is an important one. Research has shown that genes appear to increase the risk of developing UC. However, while the level of impact is unknown because there are many genetic factors involved, the chance that you will develop UC increases if you have a close family member with ulcerative colitis.

A few types of research found that 1 in 4 people have a family history of ulcerative colitis. Another indication that ulcerative colitis is associated with hereditary factors is that the disease is more likely to appear in a particular ethnic population.

Several dozens of variants are believed to contribute to this condition, with many involved in the protective barrier of the intestines. The barrier shields the tissues against the toxins that pass through your digestive system and bacteria that live in your gut. 

When this barrier breaks down, it may lead to the immune response that eventually causes ulcerative colitis. Gene mutations linked to the immune system are also likely to foster ulcerative colitis.

Is Ulcerative Colitis Genetic, or Is It Caused by Diet?

Studies of twins and families are helpful when trying to understand whether a particular disease has genetic components due to children inheriting chromosomes from their parents. With identical twins, children inherit the same genetic makeup as each other. Do they share the same genes? You could expect them to develop equivalent genetic conditions. If one of the twins develops a certain health condition and the other doesn’t, external factors are believed to influence.

Twin and family studies showed that only about 10% of the people living with ulcerative colitis have family members with a history of inflammatory bowel diseases (IBDs). The research shows that people who have a parent, child, or sibling with ulcerative colitis also have higher chances of developing the disease. These people are 4 times more likely to develop ulcerative colitis than the average person.

However, these studies also show that many people who have high genetic risk factors that increase their vulnerability to UC never develop it. In other words, your genes alone can’t be used to predict whether you will develop ulcerative colitis. Still, genetics can give clues about the location, types, and severity of ulcerative colitis symptoms in those who develop the disease.

A meta-analysis study showed that the presence of informative genes and the way they are expressed could show whether your ulcerative colitis is likely to start in the colon or the rectum. The susceptibility genes usually have roles in the intestinal epithelial cell function, immune response, or gut mucosal barrier. According to studies, these genes are displayed differently from those with ulcerative colitis compared to those who don’t have the disease.

Ulcerative Colitis and Nutrition

UC is a chronic inflammatory disease and is not thought to be caused by a person’s diet or any specific food. Some studies suggest that people who eat more sugar and saturated fat and fewer fruits and vegetables may increase their risk for UC, but the results of these studies aren’t conclusive. 

Because certain foods can cause a flare-up in symptoms, some people wonder, “Is ulcerative colitis genetic or food-related?” The support website This is Living with UC suggests avoiding these foods to prevent or deescalate a flare-up:

  • Alcohol 
  • Sugar
  • Red meat
  • Spicy foods

These foods are recommended during a flare-up:

  • Lean meats
  • Oatmeal
  • Soups and broths
  • Yogurt
  • Eggs

Maintaining good nutrition is a challenge for people living with ulcerative colitis. Symptoms can cause loss of appetite, making eating a healthy diet difficult. 

Genes Associated With Colitis Genetic

Experts have looked at several genetic changes that may be involved in ulcerative colitis. While they still don’t know how these genetic changes might result in UC, they have a few theories. Other genes linked to ulcerative colitis affect T cells. These T cells work with the immune system to identify bacteria and other foreign intruders and attack them.

 Some genetic makeups may cause T cells to either wrongly attack the bacteria that usually live in your intestine or are too aggressive to the response of toxins or pathogens passing through the colon. And the response of this immune system may contribute to developing ulcerative colitis.

A study from 2012 discovered more than seventy susceptibility genes for Inflammatory Bowel Disease (IBD). These genes have already been linked to other immune disorders such as ankylosing spondylitis and psoriasis.

IL23 (Interleukin 23) gene was initially discovered as a CD susceptibility, but it has now been confirmed in ulcerative colitis. Similarly, other members of the IL23 signaling pathway, including STAT3, JAK2, and IL12B, have consequently been linked to CD40 and then ulcerative colitis, suggesting that defective IL23 signaling poses a risk to Inflammatory bowel disease as a whole. ECM1 (Extracellular Matrix Protein 1) was indicated in a study as a key event and an active contributor behind intestinal inflammation in IBD. 

The study shows that the participation of adhesion molecules plays a significant role in the adherence of macrophages and lymphocytes to endothelial cells supporting chronic inflammation in patients with UC.

Other Risk Factors for UC

While genes play a significant role in the development of ulcerative colitis, they are just a part of the puzzle. Many people who develop ulcerative colitis have no family history. Environmental factors are likely important to UC development, and more environmental factors also trigger the condition.

Possible triggers for UC include:

  • A lack of exposure to germs and bacteria in childhood (known as the hygiene hypothesis)
  • A diet high in red meat, fat, sugar
  • Vitamin D deficiency
  • Overexposure to antibiotics in childhood
  • Overuse of nonsteroidal anti-inflammatory drugs and aspirin
  • Viral and bacterial infections such as Salmonella or measles

It is not currently known if or how triggers work together or relate to other potential environmental factors to cause UC, but it is thought that more than one is likely involved. Some environmental factors include smoking, Nonsteroidal Anti-Inflammatory Drugs (NSAIDs), Antibiotics, Contraceptive Pill, and Geographic Location.


UC is more common among certain ethnic groups. Jewish people of European descent (Ashkenazi Jews) and Caucasians are more likely to develop ulcerative colitis than other ethnicities. 


When your body feels stressed, it launches a fight-or-flight response that stimulates the immune system. While the chemical processes that happen during fight-or-flight aren’t normally harmful, a stimulated immune system can be a problem for people with ulcerative colitis. 

Stress may not cause UC, but it can trigger flare-ups. Health experts suggest developing new strategies for the way you manage stress. Suggestions for stress reduction include:

  • Meditation
  • Yoga
  • Self-care
  • Biofeedback
  • Exercise

Eating a simple but nutritious diet during stressful periods may also help you avoid a flare-up. 

Signs and Symptoms of UC

According to the National Institutes of Health, about 700,000 people in the U.S. have UC. Symptoms may vary depending on the severity of the disease and the precautions a person takes during flare-ups. Common symptoms include:

  • Diarrhea
  • Rectal bleeding
  • Five or more bowel movements per day in severe cases
  • Blood, mucus, or pus in stools
  • Rectal pain
  • Abdominal pain
  • Muscle spasms
  • Fever
  • Anemia
  • Joint pain and swelling
  • Inflammation in the face, especially mouth and eyes
  • Skin rashes
  • Fatigue

Ulcerative colitis is more than just frequent or uncomfortable bowel movements. It is a serious condition that can increase your risk for blood clots, colon cancer, arthritis, and bowel perforation. As you can see, diagnosing UC early and getting treatment is crucial for good health. The ulcerative colitis-genetic link may help people get diagnosed before symptoms become severe. 


UC has the highest prevalence in North America and Northern Europe, suggesting that a Western diet plays a vital role in UC. The disease has a case rate of 9 to 20 per one hundred persons in a year, and its occurrence is 156 situations per one hundred persons in a year. 

Out of the inflammatory bowel diseases, UC is more common in adults. The age of inception is usually between 15-30 years, with the 2nd onset between 50-70 years. Many studies also suggest that ulcerative colitis uniformly affects both men and women. It has been shown that removing the appendix before the age of 20 is linked to a decreased risk of UC.

Frequently Asked Questions About Ulcerative Colitis

1. I have celiac disease — does that mean I am also genetically predisposed to UC?

There is a strong genetic component to celiac disease. Numerous genetic variants can increase your risk of developing the disease. A meta-analysis published by the National Institutes of Health concluded that people with celiac disease have a higher risk of developing UC and other autoimmune conditions. 

2. My sister has ulcerative colitis — should I have a DNA test to see if I have it too?

A DNA test is not diagnostic. DNA testing can tell you if you have an increased risk for some diseases, but not if you will or do have that condition. You need to see a doctor for a diagnosis and treatment options. A UC diagnosis typically requires a clinical history, a study of symptoms, and diagnostic testing. 

3. Does UC increase the risk for colon cancer?

Unfortunately, yes. Inflammatory bowel conditions like UC and Crohn's disease increase your risk for colorectal cancer. Colon cancer is considered genetic and hereditary. If you have family members with colon cancer, you are at a higher risk of developing the disease. 

Genetic testing can ascertain if you have the mutations associated with colon cancer. 

 Can I Get a Genetic Test for UC?

Is ulcerative colitis genetic? Yes, there is a genetic component to this disease. However, there is currently no routine genetic test for ulcerative colitis. If you have a family member with UC or are experiencing symptoms, see your doctor. If UC is suspected, you will be referred to a gastrointestinal specialist. 

Diagnosing UC can be difficult and may take time. However, you can make changes in your diet and stress management routine that may alleviate mild symptoms even without an official diagnosis. 


Tomohiro Takano
Tomohiro Takano
Co-Founder and CEO