Coloboma means that part of the tissue that makes up the eye is missing. It’s a condition that people are born with — and it can affect 1 eye or both eyes. Scientists think coloboma is caused by changes in the genes that control eye development.
How do genes cause coloboma?
Genes are like an instruction manual — during pregnancy, they tell the baby’s body how to grow and develop. Coloboma happens when certain genes send the wrong instructions, so the eyes don’t develop correctly.
Scientists have found some of the genes that can cause coloboma. These same genes can also cause related eye conditions called anophthalmia and microphthalmia. But in most cases, experts still aren’t sure which genes cause coloboma.
Coloboma can also be a symptom of other genetic conditions that affect many parts of the body, like CHARGE syndrome.
If I have coloboma, can I pass it down to my child?
Maybe — some cases of coloboma are inherited, meaning that parents pass the condition down to their children. A child is more likely to be born with coloboma if 1 or both of their parents have it.
There’s still a lot experts don’t know about how coloboma gets passed down in families. Sometimes families with many cases of coloboma have children without the condition. And sometimes children are born with coloboma even if no one else in their family has it.
Even if a couple has a high risk of having a child with coloboma, doctors can’t predict what type they will have or how severe it will be. Learn more about the different types of coloboma.
If coloboma runs in your family, you can talk with your doctor or a specialist called a genetic counselor to learn more about the risk of passing coloboma down to your child.
Is there a genetic test for coloboma?
There’s no genetic test specifically for coloboma. Eye doctors can diagnose coloboma with a dilated eye exam. But if your child’s doctor thinks they may have another genetic condition that causes coloboma, like CHARGE syndrome, they may recommend a genetic test to diagnose that condition.