In recent years, personalized or predicative medicine is a subject to heated discussion for scientists of many countries. According to estimates, this approach can significantly improve the quality of treatment of a given person. The article presents the literature review on the clinical polymorphism of atopic dermatitis and ichthyosis vulgaris upon mutations in filaggrin gene. Certain mutations in the filaggrin gene manifest as ichthyosis vulgaris in some families, while in other ones the same mutations manifest in the form of atopic dermatitis. In the third group of families, a combination of both diseases occurs. Mutations in the filaggrin gene is a confirmed genetic risk factor for atopic dermatitis, involved in the early stages of the development of this disease and contributing to its chronicity. The identification of these mutations provides the potential for effective targeted preventive intervention and treatment. The article presents the description of our own clinical observations. The authors believe that genotyping for 2282del4 and R501X mutations in filaggrin gene is advisable in all patients with atopic dermatitis and ichthyosis vulgaris, as it enables making changes to the plan of managing patients who are carriers of the above mutations. Family history and genotyping can be used to identify children who are carriers of these mutations (in the families of patients with mutations) and to take targeted primary and individual preventive measures.