The primary open-angle glaucomas are a group of diseases, that have in common characteristic morphological changes at the optic nerve head and retinal nerve fiber layer, progressive retinal ganglion cells death and characteristic visual field loss. The risk for primary open angle glaucoma increases continuously with the level of the intra-ocular pressure. The disease advances slowly and there are no symptoms. Primary open angle glaucoma is caused by abnormal aqueous humor outflow in the trabecular meshwork in the open angle. Etiopathogenesis of primary open angle glaucoma is unclear. The increased risk of glaucoma in first degree relatives has long been recognized. Frequency of the manifestation of the disease is 10-30% in family members. The discovery of the specific genetic loci responsible for the manifestation of glaucoma has helped us to understand its mechanism of origin and definitely confirmed the hereditary nature of this disease. Digito-palmar dermatoglyphs were already used to determine hereditary base of many diseases and it was the reason for investigation of their qualitative and quantitive traits in patients with glaucoma (22 males and 23 females), their first degree relatives (19 males and 23 females) in comparison to a group of phenotypically healthy controls (52 males and 56 females). The results pointed the connection between dermatoglyphic traits of the digito-palmar complex in patients with glaucoma and the same traits of their first degree relatives. There is a possible discrimination of patients and their first degee relatives from phenotypically healthy controls, too. Therefore, it is necessary for all family members without manifestation of the disease to make a clinical examination that enables the prevention and early discovery of illness.