Filaggrin gene mutation in pediatric patients with atopic dermatitis: A look into Indian gene pool, a pilot study

Abstract

Background: Mutations in the filaggrin (FLG) gene has been reported to be an indicator of poor prognosis of atopic dermatitis (AD). It has been reported that there is a considerable variation in the mutations detected in the FLG gene in different ethnicities. Aim: To detect the presence of mutations in the FLG gene in pediatric subjects with atopic dermatitis (AD) and to compare the detected mutations with those already reported from different ethnicities. Materials and Methods: Genomic DNA extracted using standard procedure from peripheral venous blood of 30 patient and 15 control samples. Sequence analysis of the FLG gene carried out and detected changes was then cross referenced with those mutations already reported to check for novelty of detected changes. Results: Amino acid changes were detected in 28 of the patient samples and in none of the control samples indicating that changes in the FLG gene were more common in the patient group than the control group (Fishers exact test, P < 0.0001). The most commonly reported mutations R501X and 2282del4 were not detected. Only 5 of the detected 22 amino acid changes H2507Q, L2481S, K2444E, E2398Q, and S2366T have been previously reported and are not clinically significant; however, in one patient a stop codon was detected (S2366STOP). P2238N, R2239W, and V2243L detected in 70% of the samples and S2231E detected in 67% of the patient samples have not been reported so far and their clinical significance is yet to be analyzed. Conclusion: Analyses of mutations already reported showed that the changes detected from this study are novel to Indian traits. While this adds on to the minimal data available from the Indian subcontinent further analyses has to be carried out to analyze the pathogenicity of these detected changes on larger samples sizes.

Keywords

• filaggrin gene
• flg gene mutation
• molecular analysis
• pediatric atopic dermatitis