Congenital and hereditary visual impairment in Greenland

Thirty-eight cases of congenital visual impairment (CVI) were reported in the Inuit population of Greenland over a period of 40 years (1950-1989), corresponding to a frequency of 86 per 100,000 live born children. The two most common causes of blindness were optic atrophy and cerebral visual impairment due to brain disorders of various etiologies. This finding is in accordance with recently published data from the Nordic countries. On the other hand, retinopathy of prematurity and congenital cataract were rare causes of CVI in Greenland. Fifteen out of the 38 cases had unknown etiology. Genetic disorders accounted for 7/38 of the cases. A separate examination of registered cases with probable genetic visual impairment, irrespective of birth year, disclosed 25 patients. New mutations seemed to be the most reasonable explanation for isolated cases of aniridia, lens ectopia, and Down syndrome, while inbreeding was a possible contributory factor in a few autosomal recessive conditions.