Ornitine transcarbamylase (OTC) deficiency is the most common type of urea cycle disorder (UCD). It is typically passed from a mother to her child through the X chromosome. A mother who is an OTC "carrier" has one unaffected gene and one OTC gene. Some "carriers" may not know they have the OTC gene until their child is diagnosed. If your child has OTC deficiency, you may be a "carrier" of OTC deficiency as well.
If your child has OTC deficiency, contact your doctor to receive a genetic test that will determine if you are a "carrier."
In the case of mothers whose child has OTC deficiency, some "carriers" may have subtle UCD symptoms. Symptoms like headaches, confusion, trouble concentrating, and poor appetite should not be ignored. UCD symptoms can appear at any time. Even mild symptoms can mean that ammonia levels are elevated which can lead to serious health problems if not treated.
Symptoms such as headaches, vomiting, and sleepiness may be signs of high levels of ammonia building up in your blood which can lead to coma or permanent brain damage.
Download our OTC Carrier Symptom Survey to see other UCD symptoms and if they apply to you. If you have symptoms, talk with your doctor and share your completed symptom survey with him or her.
Since genes are passed down from parent to child, people in the same immediate or extended families have some of the same genes. This may include the gene that causes OTC deficiency. If one person in your family has OTC deficiency, there could be others who are affected as well. The Family Tree available here can help you see who in your family may be at risk for OTC deficiency. Take a few minutes to fill it out, then review it with your doctor or genetic counselor to see who in your family should be tested for the OTC gene. Then, learn about how to get a genetic test for you and your family, at no cost to you.
Urea cycle disorders (UCDs) are passed down through a family's genes. If your child has been diagnosed with OTC deficiency, or if you learned that you are an OTC carrier, other people in your family might also be affected. It's important to let your family members know and to give them as much information as you can about OTC and UCDs.
Starting a conversation with family members might not be easy or comfortable, but talking openly with your family about your experiences and answering their questions can give them a better understanding of the risk. You can explain what being an OTC carrier can mean to their health and suggest that they may want to get a genetic test as well. They can even get tested at no cost with our UCD Genetic Testing Program. Suggest that they talk to their doctor or genetic counselor to help them understand UCDs and learn about any symptoms they might have had.
If you don't feel comfortable talking to them in person you can take other approaches. Getting on the phone or writing a letter or email are also good options. You can compose your thoughts and all of the important information and then follow up with the personal conversation later on. Use our Talking to Your Family guide to help you get started.
Chances are, your family members will appreciate you alerting them to any potential health risks they may face