Primary Ciliary Dyskinesia: The Impact of Taste Receptor (<b><i>TAS2R38</i></b>) Gene Polymorphisms on Disease Outcome and Severity

Abstract

Background: Primary ciliary dyskinesia (PCD) is a rare genetic disease leading to recurrent respiratory infections of upper and lower airways. Chronic rhinosinusitis (CRS) and bronchiectasis are very common in PCD patients. Recently, it has been shown the presence of taste receptors in respiratory tract and the possible involvement of bitter taste receptor TAS2R38 gene in susceptibility to respiratory infections and rhinosinusitis. Objective: Aim of this study was to evaluate the frequency of TAS2R38 polymorphisms in PCD patients and their possible correlations with clinical outcomes of the disease. Methods: Genetic and phenotypic data of 35 PCD patients were collected. Clinical evaluation included neonatal respiratory distress (NRD) at birth, presence of situs inversus, CRS, and bronchiectasis. We also

Taste receptors in chronic rhinosinusitus, what is the evidence? A systematic review

“…In the study of 35 patients with PCD, the PAV/PAV diplotype was associated with less frequent respiratory exacerbations compared to patients with the PAV/AVI or AVI/AVI diplotypes 32 …”

“…However, the supertaster haplotype (PAV/PAV) for TAS2R38 correlated with an improved QoL, showing significantly lower SNOT‐22 scores 29 . For patients with PCD, a genotypic study showed a lower percentage of supertasters (PAV/PAV) with frequent respiratory exacerbations compared with tasters (PAV/AVI) and nontasters (AVI/AVI) 32 . In addition, there were no P aeruginosa infections with the supertaster (PAV/PAV) haplotype.…”

“…29 For patients with PCD, a genotypic study showed a lower percentage of supertasters (PAV/PAV) with frequent respiratory exacerbations compared with tasters (PAV/AVI) and nontasters (AVI/AVI). 32 In addition, there were no P aeruginosa infections with the supertaster (PAV/PAV) haplotype. Nonetheless, given the inherent complexity of these patient populations and limited number of studies, it is difficult to draw conclusions within these special populations.…”

“…20,21,38,40 Finally, there is a lack of institutional and geographic diversity in the included studies. Fourteen studies were done in the United States (Philadelphia [9], 12,16,18,24,26,27,29,37,39 South Carolina [1], 25 West Virginia [1], 20 Colorado [2], 38,40 and unspecified [1] 31 ), 5 in Italy, 17,19,28,30,32 1 in Canada, 21 1 in Poland, and 1 in Australia. 23 Despite the leading role of the University of Pennsylvania in pioneering this field and conducting 9 of 14 of the included US studies, increased genetic and geographic diversity of patients will be important given inherent differences in the distribution genetic of TR genes.…”

Taste Receptors: The Gatekeepers of the Airway Epithelium

“…Moreover, the frequency of the PAV allele (i.e., the functional allele) was significantly reduced in CF patients with nasal polyps that required additional sinus surgery, and in CF patients that were colonized with P. auruginosa [ 70 ]. Finally, TAS2R38 polymorphisms have also been described in patients with primary ciliary dyskinesia [ 71 ] and sweet taste receptors have been implicated in acute respiratory stress syndrome [ 45 ]. These studies demonstrate that taste receptors might contribute to physiological and pathological phenotypes and that genetic variations in these receptors might contribute to disease severity and risk.…”