Saudi Journal of Medicine and Medical Sciences

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 8  |  Issue : 3  |  Page : 188--195

TaqI and ApaI variants of Vitamin D receptor gene increase the risk of colorectal cancer in a Saudi population


Ayat B Al-Ghafari1, Khadijah S Balamash2, Huda A Al Doghaither2 
1 Department of Biochemistry, Faculty of Science; Experimental Biochemistry Unit, King Fahd Medical Research Center; Cancer and Mutagenesis Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
2 Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia

Correspondence Address:
Dr. Ayat B Al-Ghafari
Department of Biochemistry, Faculty of Science, King Abdulaziz University, P O Box 8795, Jeddah 23817
Saudi Arabia

Background: Polymorphisms in the gene encoding the vitamin D receptor (VDR) affect the protective role of vitamin D against many types of cancers, including colorectal cancer (CRC). Objective: The objective of this study was to assess the effect of four major polymorphisms of the VDR gene (ApaI, TaqI, BsmI and FokI) on the risk of CRC in a Saudi population. Materials and Methods: This case–control study recruited 132 CRC patients from the oncology clinics at King Abdulaziz University Hospital and 124 healthy controls from the blood bank at King Fahad General Hospital, Jeddah, Saudi Arabia, between September 2017 and August 2018. All participants were Saudis and aged 20–80 years. Genomic DNA samples were extracted from the peripheral blood cells and amplified with polymerase chain reaction. The resulting fragments were digested with different endonucleases to reveal the genotypes using the restriction fragment length polymorphism technique. The genotype distribution and allele frequency, odds ratio (OR), risk ratio (RR) and P values were determined with contingency table analysis following Hardy–Weinberg equilibrium equation. Results: For the ApaI single-nucleotide polymorphism (SNP) (rs7975232), only the heterozygous (Aa) genotype increased the risk of CRC (OR = 3.4, RR = 2.3, and P < 0.0001), whereas the TaqI SNP (rs731236) carriers with either the heterozygous (Tt) or homozygous (tt) genotype displayed an increased risk for the disease (OR = 6.18, RR = 4, P < 0.0001; OR = 3, RR = 2.4, P = 0.02, respectively). In contrast, heterozygous (Bb) and homozygous (bb) carriers of the BsmI SNP (rs1544410) had significantly lower risk for CRC (P < 0.0001). Finally, for the FokI SNP (rs2228570), there was no association with CRC risk. Conclusion: This study found that VDR SNPs ApaI and TaqI increase the risk of CRC, whereas BsmI reduces the risk of CRC in the selected Saudi population. Therefore, ApaI and TaqI SNPs could potentially be used as a diagnostic biomarker for CRC. However, the molecular mechanisms by which these variants increase or decrease the risk of CRC need to be investigated.


How to cite this article:
Al-Ghafari AB, Balamash KS, Al Doghaither HA. TaqI and ApaI variants of Vitamin D receptor gene increase the risk of colorectal cancer in a Saudi population.Saudi J Med Med Sci 2020;8:188-195


How to cite this URL:
Al-Ghafari AB, Balamash KS, Al Doghaither HA. TaqI and ApaI variants of Vitamin D receptor gene increase the risk of colorectal cancer in a Saudi population. Saudi J Med Med Sci [serial online] 2020 [cited 2020 Sep 27 ];8:188-195
Available from: http://www.sjmms.net/article.asp?issn=1658-631X;year=2020;volume=8;issue=3;spage=188;epage=195;aulast=Al-Ghafari;type=0