Methods: The case-control samples of 32 severe AD patients and 20 normal individuals were recruited from the Childhood Asthma Atopy Center of Asan Medical Center, diagnosed by physician. The cases and controls were sequenced by Illumina Hi-Seq 2500 with Agilent SureSelectXT Human ALL Exon V4+UTR Kit. Sequence alignment was performed using Burrows-Wheeler Aligner. Variants were called using Genome Analysis Toolkit (GATK). We identified 233,254 single nucleotide variants (SNVs), of which 131,321 SNVs passed quality control criteria (HWE p-value<10-3, Missing rate >10%, Minor allele count <2). Of these, 34,991 variants were non-synonymous SNPs. A Chi-square test was conducted to find disease-associated variants.
Results: We identified three missense variants in a 112bp window at ZNF443(p-value<10-4). For p-value<10-2, 137 missense variants were discovered. Among them, 2 variants at NLRP10 and CYP24A1 were located nearby previously reported AD associated regions. Functional enrichment analysis showed that 47 SNVs were related with immune related genes such as ZBP1, FBXO38, MTR, TTN.
Conclusion:In summary, we identified 137 missense variants susceptible to AD and replicated 2 previously reported loci. To validate the genetic effect of discovered variants, the replication analysis in an independent cohort is required.