Spontaneous and Inheritable R555Q Mutation in the TGFBI/BIGH3 Gene in Two Unrelated Families Exhibiting Bowman's Layer Corneal Dystrophy

The R555Q mutation occurred spontaneously and independently in the 2 unrelated CDB families and was confirmed to be transmitted to the next generation in 1 of the 2 families. These findings strongly support the notion that a genetic diagnosis should be determined for CDB and other dystrophies associated with mutations in TGFBI/BIGH3. The discovery of a spontaneous mutation should alert clinicians to be aware of the existence of genetic alterations for their patients without apparent family history of the disease.