Eye and ocular adnexa manifestations of MED12-related disorders.

BACKGROUND

-related disorders are a rare group of intellectual disability syndromes with a broad range of phenotypic characteristics. The phenotypic spectrum of -related disorders currently includes X-Linked Ohdo Syndrome, Lujan-Fryns Syndrome (LS), and FG syndrome type 1 (FG), also known as Opitz-Kaveggia Syndrome. The gene encodes the largest component of the mediator complex of RNA polymerase II, which is critical for recruiting activators and repressors to regulate the transcription of genes critical to growth, development, and differentiation.

METHODS

We performed a systematic literature review of previously published cases to highlight the key ocular features in individuals with -related disorders. In addition, we present a new case of a female patient with a pathogenic c. 3866A>G, p.Q1289R variant. Ocular manifestations are not uncommon in -related disorders, but have not been characterized in literature reports. Commonly reoccurring reported eye and ocular adnexa features within the spectrum include ptosis, downslanting palpebral fissures, and hypertelorism. Other less common findings include strabismus, astigmatism, and optic nerve hypoplasia.

RESULTS

Our patient presented with developmental delay, mild hypotonia and dysmorphic features including frontal bossing, high arched palate, and syndactyly of the 2 and 3 toes bilaterally.

DISCUSSION

Ocular manifestations identified in this patient included intermittent esotropia, hyperopic astigmatism, epicanthal folds and ptosis bilaterally.