Multitissue Integrative Analysis Identifies Susceptibility Genes for Atopic Dermatitis

Area of Science:

• Genetics
• Dermatology
• Immunology

Background:

• Atopic dermatitis (AD) is a complex inflammatory skin disease with known genetic and environmental factors.
• Genome-wide association studies (GWASs) have identified AD susceptibility loci, but explain limited phenotypic variation.

Purpose of the Study:

• To identify additional susceptibility genes for atopic dermatitis (AD).
• To investigate putatively causal genes for AD using transcriptome-wide association studies and Mendelian randomization.

Main Methods:

• Conducted a large-scale transcriptome-wide association study (TWAS) in approximately 840,000 European individuals.
• Utilized a joint-tissue imputation approach with gene expression data from AD-relevant tissues (skin fibroblast, lymphocyte, whole blood).
• Performed Mendelian randomization (MR) causal inference analysis on TWAS-identified genes.

Main Results:

• Identified 51 genes significantly associated with AD after Bonferroni correction.
• Discovered 19 genes with putatively causal associations, including the known FLG gene and seven novel genes like AQP3 and PDCD1.
• Validated four genes (AQP3, PDCD1, ADCY3, DOLPP1) through differential expression or Mouse Genome Informatics data.

Conclusions:

• This study successfully identified novel susceptibility genes for atopic dermatitis (AD).
• The findings provide new genetic clues for understanding the underlying mechanisms of AD.
• The identified genes, particularly novel ones like AQP3 and PDCD1, warrant further investigation in AD pathogenesis.