A mother and her daughter had hereditary benign intraepithelial dyskeratosis of the bulbar conjunctiva. The daughter's lesions were studied histologically; they were quite similar to those previously described of patients living in Halifax County, North Carolina. The patient, however, had always lived in Philadelphia. Since the patient's lesions were clinically and histologically so like those in other patients previously reported from North Carolina, an environmental factor (or factors) is considered highly unlikely; the entity is genetically transmitted as a simple mendelian dominant. This case illustrates the importance of the awareness of genetically determined diseases that may be introduced into communities where they had not existed previously.
Yanoff M. Hereditary Benign Intraepithelial Dyskeratosis. Arch Ophthalmol. 1968;79(3):291-293. doi:10.1001/archopht.1968.03850040293012