Bilateral Brown syndrome in monozygotic twins

Area of Science:

• Ophthalmology
• Genetics
• Pediatrics

Background:

• Brown syndrome is a rare congenital disorder affecting eye movement, characterized by limited elevation of the eye in adduction.
• Most reported cases of Brown syndrome are sporadic and affect only one eye (unilateral).
• Familial occurrences are exceptionally rare, making genetic contributions poorly understood.

Observation:

• A unique case of monozygotic (identical) twins presenting with congenital bilateral Brown syndrome is described.
• Both twins exhibited the characteristic symptoms of limited eye elevation in adduction in both eyes.
• This presentation is highly unusual given the typically sporadic and unilateral nature of the condition.

Findings:

• This is the first documented instance of congenital bilateral Brown syndrome occurring in monozygotic twins.
• The observation suggests a potential, albeit rare, genetic predisposition or shared environmental factor in the etiology of Brown syndrome.
• Review of prior familial cases supports the rarity of genetic transmission.

Implications:

• This case provides valuable insights into the potential genetic underpinnings of Brown syndrome.
• Further research into the genetic factors influencing binocular Brown syndrome in twins may elucidate disease mechanisms.
• Understanding these rare familial patterns can aid in genetic counseling and future diagnostic approaches for congenital eye movement disorders.