The role of filaggrin mutations leading to a decrease in the amount of protein in the development of atopic dermatitis and bronchial asthma in children

Atopic diseases remain one of the most common childhood diseases. At the beginning of life, atopic dermatitis (AD) occurs, and only then bronchial asthma (BA). This staged development of sensitization and transformation of clinical manifestations is called the atopic march. Are the genetic factors of predisposition to AD the same for BA? There is still no definite answer to this question. Mutations in the filaggrin gene (FLG) are known to impair skin barrier function. Filaggrin is expressed not only in the skin, but also in the respiratory organs of the nasal mucosa, lungs, and bronchi. Filaggrin defects lead not only to disruption of the skin barrier, but also to an increase in the Th2 response and increased production of IgE, typical of bronchial asthma. Therefore, mutations in the FLG gene can be a risk factor for the development of not only AD, but also BA.

The aim of this study was to compare the values of the association of mutations in the FLG gene with AD and BA in the Russian sample.

Material and methods. Case-control study design. We used 265 blood samples from children. 4 mutations in the filaggrin gene were identified by real-time PCR. The association of mutations with disease was assessed by odds ratio.

Results. We showed a strongly pronounced association of the deletion of 4 nucleotides (2282del4) with AD, but not with BA, although for patients with atopic BA the indicator of the association of this mutation with the disease was higher than for the group with symptoms of bronchial asthma identified by the ISAAC questionnaire. These results lead to the conclusion that the role of the filaggrin gene for BA is much less significant than for AD.

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