Purpose: Polymorphisms in the vitamin D receptor (VDR) gene may be of etiological importance in determining cancer risk. The aim of this study was to assess the association between common VDR gene polymorphisms and esophageal adenocarcinoma (EAC) risk in an all-Ireland population-based case-control study. Methods: EAC cases and frequency-matched controls by age and gender recruited between March 2002 and December 2004 throughout Ireland were included. Participants were interviewed, and a blood sample collected for DNA extraction. Twenty-seven single nucleotide polymorphisms in the VDR gene were genotyped using Sequenom or TaqMan assays while the poly(A) microsatellite was genotyped by fluorescent fragment analysis. Unconditional logistic regression was applied to assess the association between VDR polymorphisms and EAC risk. Results: A total of 224 cases of EAC and 256 controls were involved in analyses. After adjustment for potential confounders, TT homozygotes at rs2238139 and rs2107301 had significantly reduced risks of EAC compared with CC homozygotes. In contrast, SS alleles of the poly(A) microsatellite had significantly elevated risks of EAC compared with SL/LL alleles. However, following permutation analyses to adjust for multiple comparisons, no significant associations were observed between any VDR gene polymorphism and EAC risk. Conclusions: VDR gene polymorphisms were not significantly associated with EAC development in this Irish population. Confirmation is required from larger studies.
The FINBAR study group members include LJ Murray (Queen’s University Belfast), LA Anderson (Queen’s University Belfast), BT Johnston (Belfast Health & Social Care Trust), RGP Watson (Belfast Health & Social Care Trust), J McGuigan (Belfast Health & Social Care Trust), HR Ferguson (Belfast Health & Social Care Trust), SJ Murphy (St Vincent’s Hospital Dublin), JV Reynolds (St James’ Hospital, Dublin) and H Comber (National Cancer Registry of Ireland). We appreciate the contributions made by the study participants, their families and all who assisted with the study, particularly the Northern Ireland Cancer Registry and National Cancer Registry Cork. This research was supported by funding from the Ulster Cancer Foundation, the Northern Ireland R&D office and the Health Research Board.
- Case-control studies
- Esophageal adenocarcinoma
- Single nucleotide
- Vitamin D receptor