Congenital fibrosis of the extraocular muscles (CFEOM) affects cranial nerves 3 and 4 and is caused by autosomal dominant missense variants in KIF21A, TUBB3, TUBB2B or TUBA1A or autosomal recessive variants in PHOX2A (9, 10, 12, 86, 87). This evidence concerns the gene TUBB3 and congenital fibrosis of the extraocular muscles.