Introduction. Increasing attention has recently been paid to studying the filaggrin gene (FLG; filaggrin) as a major genetic marker of predisposition to atopic dermatitis (AD). Objective. To assess the frequency of 2282del4 and R501X FLG mutations in the FLG gene in AD patients and their family members. Material and methods. The results of genetic study of 86 patients with atopic dermatitis and/or their family members for the presence of FLG gene mutations are reported. Results and discussion. FLG gene polymorphism in AD patients and their families was found in 23.26±4.58% of cases. The 2282del4 mutation in the heterozygous FLG gene (N/2282del4) is registered most frequently (85.00±8.19%). There are "clinically healthy" persons among the carriers of defective FLG genes, mostly children (30.00±10.51%). Conclusions. Abnormal polymorphism of the FLG gene among AD patients and their families occurs in 23.26±4.58% of cases. Among the FLG gene mutations, 2282del4 mutation in the heterozygous FLG gene (N/2282del4) occurs most frequently (85.00±8.19%). AD patients with FLG mutations have more severe disease progression and poor prognosis. Eight types of causal relationship between the presence of genetic defects, family history and clinical manifestations of AD were distinguished. There are "clinically healthy" persons among the carriers of defective FLG genes, mostly children (30.00±10.51%).