Background Susceptibility to asthma is known to involve genetic factors. Genome-wide screens have indicated that the chromosome 5q31–q34 region is linked to and/or associated with asthma. A new gene, named UGRP1 and reported by Niimi et al., encodes uteroglobin-related protein and is expressed in the lung and trachea. Niimi et al. showed the −112G/A polymorphism of the UGRP1 gene to be associated with asthma in a case–control study.
Objective The objective of the present study was to replicate this association and confirm the possible role of the UGRP1−112G/A polymorphism in the aetiology of childhood asthma in a Japanese population.
Methods and results We conducted a transmission disequilibrium test (TDT) in 131 families identified through paediatric patients being treated for asthma. A case–control study was also carried out by comparing the probands and 137 unrelated non-atopic non-asthmatic Japanese children and 211 unrelated healthy Japanese adults. The −112G/A polymorphism was genotyped by the PCR-RFLP method. The TDT revealed that the −112A allele was not preferentially transmitted to asthma-affected children (P=0.85). Neither the presence of at least one A allele in an individual's genotype (sum of the G/A and A/A genotypes) nor the −112A allele was more prevalent among the asthma subjects than among the control subjects.
Conclusion Our findings indicate that the UGRP1−112G/A polymorphism does not play a substantial role in genetic predisposition to childhood asthma in this Japanese population.