Abstract
Purpose: :
We analyzed mutations of genes causing congenital fibrosis of the extraocular muscles (CFEOM) and similar disorders.
Methods: :
After a full explanation of the genetic analysis, informed consent was obtained from 5 patients with CFEOM, 1 with congenital absence of the inferior rectus muscle, 3 with congenital oculomotor palsy, and 1 with double elevator palsy. Blood samples were collected for DNA extraction, followed by genetic analysis via direct sequencing of the ARIX (exons 1a, 1b, 2, 3a, and 3b), KIF21A (exons 8, 20, and 21), and PHOX2B (exons 1, 2, 3a, and 3b) genes responsible for CFEOM.
Results: :
Two patients with CFEOM were found to have mutations: the 2 patients had G153A in the ARIX region (exon 1a); 1, G2861A in the KIF21A region (exon 21); and 2, A1121C in the PHOX2B region (exon 3). In contrast, no mutations were detected in the patients with congenital absence of the inferior rectus muscle, congenital oculomotor palsy, or double elevator palsy.
Conclusions: :
The mutations observed in CFEOM were not detected in similar disorders, suggesting that CFEOM is genetically different from other diseases causing strabismus.
Keywords: strabismus: diagnosis and detection • gene screening • genetics