Figure 4.

rs11603634 is an eQTL for MUC5AC in bronchial epithelial brush samples and MUC5AC mRNA expression is increased in bronchial epithelial cells from severe asthma patients

(A) MUC5AC mRNA expression stratified by rs11602802 genotype. The boxes show the mean and SD and the whiskers show the IQR for each genotype. Generated from bronchial epithelial brush samples (n=117) collected as part of the U-BIOPRED study. rs11603634 was not directly genotyped, so the proxy rs11602802 was used. The rs11603634 asthma risk allele, G, is correlated with rs11602802, A, allele. (B) mRNA expression of MUC5AC in the GSE43696 dataset.⁴¹ Boxes showing the median and IQR, and the whiskers showing the minimum and maximum data, stratified by subject group. Bronchial epithelial brush samples were from controls (n=20), and patients with mild or moderate (n=50) and severe (n=38) asthma from the GSE43696 dataset and GC-RMA data for MUC5AC. MUC5AC levels were significantly higher in patients with severe asthma than in controls. (C) mRNA expression of MUC5AC in the GSE89809⁴² dataset. The boxes show the median and IQR, and the whiskers showing the minimum and maximum data, stratified by subject group. Bronchial epithelial brush samples were from controls (n=18), and patients with mild (n=14), moderate (n=13), and severe (n=11) asthma from the GSE89809 dataset and GC-RMA data for MUC5AC was extracted. MUC5AC RNA concentrations were significantly higher in patients with severe asthma than in controls. More details of datasets and analyses are in the appendix. eQTL=expression quantitative trait loci. GC-RMA=GeneChip robust multi-array average. U-BIOPRED=Unbiased BIOmarkers in PREDiction of respiratory disease outcomes. *p<0·05 by Kruskal-Wallace test.