MACS Conditions

MACS conditions affect eye development before birth and can impact vision in various ways. They include:

• Microphthalmia – A condition where one (unilateral) or both (bilateral) eyes are smaller than usual and may have structural differences. Some children may be blind, while others retain some vision.
• Anophthalmia – The complete absence of one or both eyes. This affects the development of the eye socket, leading to differences in eyelid size or facial structure.
• Coloboma – A gap in one or more parts of the eye (such as the iris, retina, or optic disc) due to incomplete development during pregnancy. The effect on vision varies depending on the size and location of the gap. Doctors can better assess its impact as a child grows.

How Do These Conditions Occur?

The exact causes of Microphthalmia and Anophthalmia are still being researched, but they likely result from disruptions in early eye development. These can be influenced by:

• Genetics – More than 90 genes have been linked to MAC conditions. Scientists continue to study how these genes affect eye formation.
• External Factors – Certain infections during pregnancy (e.g., rubella or chickenpox) and medications (e.g., thalidomide) have been linked to these conditions. Environmental factors like exposure to insecticides or fungicides may also play a role.
• Coloboma – This occurs when a natural gap in the developing eye doesn’t close fully before birth, leaving a cleft in the eye structures.

Key Statistics

• Approximately 114 children are born with MACS conditions each year in the UK.
• These conditions may involve vision loss, developmental challenges, or other congenital differences.
• Over 90 genes have been linked to MAC conditions, highlighting the complexity of eye development before birth.