Promoter Genotyping and mRNA Expression - Based Analysis of the PTGDR Gene in Allergy
San Segundo-Val I1, García-Sánchez A2,3, Sanz C2,4, Cornejo-García JA5, Isidoro-García M1,2,6, Dávila I2,3,7
1Department of Clinical Biochemistry, University Hospital of Salamanca, Salamanca, Spain
2Institute for Biomedical Research of Salamanca, Salamanca, Spain
3Department of Biomedical Sciences and Diagnostics, University of Salamanca, Salamanca, Spain
4Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
5Research Laboratory, IBIMA, Regional University Hospital of Malaga, UMA, Malaga, Spain
6Department of Medicine, University of Salamanca, Salamanca, Spain
7Department of Allergy, University Hospital of Salamanca, Salamanca, Spain
J Investig Allergol Clin Immunol 2020; Vol 30(2)
Background: Prostaglandin D2 receptors are acquiring a relevant role as potential therapeutic targets in allergy. PTGDR has been described as a candidate gene in allergic disease, although functional studies on this gene are lacking.
Objective: The objective of this case-control study was to investigate the potential role of PTGDR in allergy.
Methods: The study population comprised 195 allergic patients and 112 healthy controls. The PTGDR promoter polymorphisms –1289G>A, –1122T>C, –881C>T, –834C>T, –613C>T, –549T>C, –441C>T, –197T>C, and -95G>T were amplified by polymerase chain reaction (PCR) and sequenced. PTGDR expression levels were analyzed using quantitative PCR and normalized to GAPDH and TBP mRNA levels. All procedures were performed following the Minimum Information for Publication of Quantitative Real-Time PCR Experiment guidelines.
Results: PTGDR expression levels were significantly higher in allergic patients than in controls (P<.001). Receiver operating characteristic analysis for expression of PTGDR showed a sensitivity of 81.4% compared with 67% for IgE levels. In addition, differences in the genotypic distribution of the polymorphisms –1289G>A and –1122T>C were found in allergic patients (P=.009).
Conclusions: The results indicate that PTGDR overexpression is associated with allergy. The polymorphisms –1289G>A and –1122T>C partly explain the variation in expression we observed. PTGDR expression could have a potential role as a biomarker and pharmacogenetic factor in allergy.
Key words: Allergy, Asthma, mRNA expression, Polymorphisms, PTGDR, Rhinitis