Ocular adnexal phenotype and management of a patient with mosaic expression of a mutation in TWIST2

ABSTRACT

Ablepharon-macrostomia syndrome (AMS) and Barber-Say syndrome (BSS) are congenital ectodermal dysplasias associated with mutations in the TWIST2 gene. Among the ophthalmic anomalies that occur in these syndromes, underdevelopment of the anterior lamella of the eyelid is a defining feature. Reports of mosaic expression of TWIST2 mutations are extremely rare, with only five confirmed or suspected cases described to date. Mosaic expression of TWIST2 variants is correlated with a less severe phenotype than that reported for the typical expression of TWIST2 variants associated with BSS or AMS. Abnormal development of the anterior lamella appears to be a common feature in all cases of AMS with mosaic expression. Here, we describe the phenotype of a patient with mosaic expression of a TWIST2 mutation that is typically associated with AMS. We additionally describe the surgical approach employed in the treatment of this patient.

KEYWORDS:

• Ablepharon-macrostomia
• anterior lamella
• Barber-Say
• eyelid coloboma
• mosaic

Disclosure statement

Author Louise A. Mawn, MD, is an advisor to Horizon Therapeutics.

Meeting presentation

This case was presented at the ASOPRS 50th Anniversary Fall Scientific Symposium, San Francisco, 2019.

Additional information

Funding

THis work was supported by the Research to Prevent Blindness, unrestricted departmental award Vanderbilt University Medical Center, Department of Ophthalmology & Visual Sciences .