CDHR3 (cadherin-related family member 3) is a transmembrane protein that is highly expressed in airway epithelia and the only known receptor for rhinovirus C (RV-C).
Genotyping of 41 chimpanzees and examination of 24 published chimpanzee genomes from subspecies across Africa showed universal homozygosity for the cadherin-related family member 3CDHR3-Y<sub>529</sub> allele, which increases risk for rhinovirus C infection and asthma in human children.
Studies on rhinovirus species (RV)-C infection have found that this is associated with a decrease in expression of CDHR3, the cellular receptor specific for this virus, and a decrease in interferon-β expression, both of which are likely to favour RV-C infection.
The aim of this study was to examine rs6967330 genotypes and mRNA expression of CDHR3 in relation to presence of rhinovirus and clinical symptoms in children with acute wheezing and compare to a group of age-matched healthy children.
Recently, the receptor for the virulent RV-C CDHR3, was identified, but a dearth of studies have examined RV-C-induced effects in humans.Currently, the mechanisms by which RV infections modulate airway smooth muscle (ASM) shortening or excitation-contraction coupling remain elusive.
Recent studies have demonstrated that a coding SNP (rs6967330, Cys529→Tyr) in cadherin-related family member 3 (CDHR3), which was previously associated with wheezing illness and hospitalizations in infancy, could support efficient human rhinovirus C (RV-C) entry and replication.
Progress has also been made in elucidating the genetic risk factors for asthma exacerbations, most notably the contribution of the ORMDL3/GSDMB locus on 17q, the mechanisms underlying the farming effect, and the discovery that CDHR3 binds to rhinovirus species C.