Loading
Microtia is a congenital deformity in which the external ear (auricle) is small, underdeveloped, or completely absent. It usually affects one ear but can also be bilateral. The severity ranges from mild ear abnormalities to complete absence (anotia).
The exact cause of microtia is often unknown. However, genetic factors may play a role in some cases.
If there’s a family history of microtia or other ear anomalies, the risk may increase.
Microtia can occur as part of genetic syndromes such as Treacher Collins or Goldenhar Syndrome.
Most cases are sporadic, meaning they occur randomly without a clear hereditary pattern.
Microtia is not always genetic. Other factors that may increase the risk include:
Viral infections during pregnancy (e.g., rubella)
Certain medications or toxins taken during early pregnancy
Vitamin A deficiency or excess
Maternal diabetes
Environmental exposures such as radiation or chemicals
These factors can affect the development of the baby’s ears during the first trimester.
Microtia can be hereditary in rare cases. It may follow an autosomal dominant pattern in certain genetic syndromes. However, the majority of cases occur in children with no family history of the condition.
If a parent or sibling has microtia, the recurrence risk is estimated to be 5–10%.
You may be referred for genetic counseling if:
There are other family members with microtia
The child has other congenital anomalies
A genetic syndrome is suspected
Genetic testing can help determine if there’s an underlying syndrome or inherited pattern.
Microtia cannot always be prevented, but risks can be reduced by:
Receiving proper prenatal care
Avoiding harmful substances during pregnancy
Using vitamins only under medical supervision
Avoiding consanguineous (close-relative) marriages
Seeking genetic counseling before pregnancy if there's a family history
Is microtia caused by genetics or the environment?
Both can be factors. Some cases are inherited, while most occur sporadically due to unknown or environmental causes.
Can microtia run in families?
Yes, but rarely. If multiple family members are affected, a genetic evaluation is recommended.
Should I get genetic testing?
If microtia is accompanied by other physical anomalies or there's a family history, genetic testing can provide helpful insights.
If you'd like to learn more about the genetic causes of microtia or receive a personalized consultation, feel free to contact our clinic today.
