This paper presents some characteristics of the population genetics of primary congenital glaucoma in Slovakia. The overall incidence in Slovakia is 1:10,500, while being 1:1,250 in the Gypsy subpopulation of Slovakia and 1:22,000 in the non-Gypsy population. For a special type of congenital primary glaucoma, transmitted by autosomal recessive inheritance in Gypsies the gene frequency may be estimated to reach 2.8%. Early onset of the disease enabling diagnosis soon after birth in 82% of patients may be considered another characteristic of this type of primary congenital glaucoma.