Association of Toll-Like Receptor Polymorphisms With Nasal Polyposis

Risk Prediction of Chronic Rhinosinusitis with or without Nasal Polyps in Taiwanese Population Using Polygenic Risk Score for Nasal Polyps

The association between single nucleotide polymorphisms and chronic rhinosinusitis (CRS) has been determined. However, it was not known whether the polygenic risk score (PRS) for nasal polyps (NP) could predict CRS with NP (CRSwNP) or without NP (CRSsNP). The aim of this study was to investigate the association between PRSs for NP and the risk of CRS with or without NP. Data from 535 individuals with CRS and 5350 control subjects in the Taiwan Precision Medicine Initiative project were collected. Four PRSs for NP, including PGS000933, PGS000934, PGS001848, and PGS002060 from UK Biobank, were tested in these participants. They were divided into four groups according to quartiles of PRSs. The logistic regression model was performed to evaluate CRSwNP and CRSsNP risk according to PRSs for NP. The PGS002060 had the highest area under the curve at 0.534 for CRSsNP prediction and at 0.588 for CRSwNP prediction. Compared to subjects in the lowest PRS category, the PGS002060 significantly increased the odds for CRSsNP by 1.48 at the highest quintile (p = 0.003) and by 2.32 at the highest quintile for CRSwNP (p = 0.002). In addition, the odds for CRSwNP increased by 3.01 times in female CRSwNP patients (p = 0.009) at the highest quintile compared with those in the lowest PRS category. The PRSs for NP developed from European populations could be applied to the Taiwanese population to predict CRS risk, especially for female CRSwNP.

Genetics and epigenetics of chronic rhinosinusitis

Discerning the genetics and epigenetics of chronic rhinosinusitis (CRS) may optimize outcomes through early diagnostics, personalized and novel therapeutics, and early prognostication. CRS associated with cystic fibrosis and primary ciliary dyskinesia has well-characterized genetic mutations. Most CRS subjects, however, do not exhibit identifiable monogenic alterations. Clustering in related individuals is seen in CRS with nasal polyps. Spouses of subjects with CRS without nasal polyps also may be at increased risk of the same disease. These observations generate questions on genetic and environmental influences in CRS. Genome-wide association studies have identified variations and polymorphisms between CRS and control subjects in genes related to innate and adaptive immunity. Candidate gene and transcriptomics studies have investigated and identified genetic variations related to immunity, inflammation, epithelial barrier function, stress-response, antigen processing, T-cell regulation, and cytokines in CRS. Epigenetic studies have identified mechanisms through which environmental factors may affect these gene functions. However, causality is not determined for most variations. Inferences drawn from these data must be measured because most investigations report unreplicated results from small study populations. Large, replicated studies in tight cohorts across diverse populations remain a pressing need in studying CRS genetics.

Association of Toll-like receptors 4 (TLR-4) gene expression and polymorphisms in patients with severe asthma

Innate immunity plays a central role in the pathogenesis of severe asthma, and it is closely linked to elevated IgE and Toll-like receptor 4 (TLR-4) levels. However, there is a scarcity of information about the association of the TLR-4 receptor polymorphism in the pathogenesis of severe asthma. This study highlights the level of gene expression of different alleles in asthmatic patients compared to healthy control individuals. This was a randomized control trial, which included 150 patients with asthma (with high serum levels of IgE) with a matching 150 healthy control individuals. Participants had a series of blood tests to measure various immune parameters: interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor (TNF), intercellular adhesion molecule-1 (ICAM1) and detect allele type and gene expression of the TLR-4 gene. Patients with asthma had significantly higher levels of IL-8 when compared to the healthy control participants. In addition, in the rs91 genotyping, there were significant differences in the levels of IL-8 and TNF between CC and TT genotyping. While in rs90 TLR-4, TNF levels were significantly higher in AA vs. AG and GG genotypes among the asthmatic patients when compared to the control group. The results showed that in TLR-4, rs4986791 were significantly associated with asthma risk. Polymorphisms in TLRs play essential roles in asthma.