Anterior chamber depth, genes and environment. A population study among long-term Greenland Eskimo immigrants in Copenhagen

Abstract

Previous population studies have demonstrated a shallow anterior chamber as an inherited characteristic of Eskimos, explaining their high prevalence of primary angle-closure glaucoma. In order to evaluate the stability of the anterior chamber depth (ACD) distribution and its inherent morbidity risk in a different environment, immigrant Greenland Eskimo women in Copenhagen, aged 40 years or more were sampled. Those who had been at least 25 years in Denmark were examined (N = 64), using Haag Streit pachymetry, limbal chamber depth (LCD) estimation and gonioscopy. The ACD level of the immigrants was significantly higher than that of their background population, in ethnically 'mixed' as well as 'pure' subgroups, and correspondingly the LCD grading was higher among the immigrants. Primary angle-closure glaucoma was found in 3%. The refraction showed no significant trend towards myopia compared with native Greenland Eskimos. Environmental factors influencing ACD, e.g. through the rate of biological ageing, seem to exist, but their nature is unknown.