In the L450W mutant, Descemet's membrane was several times thicker than normal and traversed by refractile strands and blebs that stained intensely for COL8A2, a feature also observed in late-onset FCD.
The profile of age and disease severity for the L450WFCD kindred suggested that disease onset occurred in infancy, compared with an average age of onset of 50 years estimated for 201 familial FCD patients in 62 other families.
Peripheral, anterior microcystic corneal edema represents a characteristic aspect of the phenotype associated with the p.(Leu450Trp) substitution in COL8A2, in at least 2 of 3 known affected families worldwide.