Application of modern genetic and instrumental examination methods in clinical practice opens up new possibilities to assess the patient’s condition and to select the therapy, but requires the investigation of their diapason of use. The number of patients equal 333 with dermatoses and xerosis (aged from 3 months to 74 years) was examined for mutations in the genes of filaggrin (2282del4 (rs558269137), R501X (rs61816761), R2447X (rs138726443) and cytokines (IL-4 (rs2243250), TNFα (rs1800629) to determine the genetic status and morphologic state of skin in patients with ichthyosis vulgaris (IV). The indicators of ichthyosis vulgaris and atopic dermatitis (AD) were evaluated during the examination. The number of patients equal 6 (1.8%) from 333 patients with xerosis were homozygotes and 53 patients (15.9%) were heterozygotes for the 2282del4 mutation in the filaggrin gene, 2 patients (0.6%) were heterozygotes for mutation in the R501X gene, 2 patients (0.6%) were heterozygotes for mutation in the R2447X gene and 270 patients (81.1%) did not have mutations in the filaggrin gene. Ichthyosis was found in 3 (50%) patients (in 1 of them combined with AD) among homozygotes, and in 13 (24.5%) patients (in 7 of them combined with AD) among heterozygotes, and in 7 (2.6%) ones (in 4 of them combined with AD) among patients without mutation. Polymorphisms of cytokines genes, associated with AD, were revealed in patients with IV: 5 patients had IL-4-590 C/T genotype, 3 patients had TNF-α-308 G/A genotype and 1 patient had TNF-α-308 A/A genotype. All above mentioned patients did not have AD. Results of high-frequency ultrasound investigation demonstrated the presence of significant subepidermal low-echogenic band (SLEB) and dermal hypoechogenicity in patients with AD and without IV compared to patients with IV and AD.