Vitamin D and Inflammatory Bowel Disease

Table 1

Genetic polymorphisms and IBD (chronological order).

Author	Year	Population	Investigated gene polymorphisms	Main findings
Single- or multicenter studies
Simmons et al. [23]	2000	England 158 UC, 245 CD,; 164 CRADC	VDR: TaqI, ApaI, FokI	TaqI polymorphism (“tt” genotype) more frequent in CD compared to UC or controls
Martin et al. [24]	2002	Germany, 95 CD, 93 UC, 119 HC	VDR: TaqI	TaqI (“tt” genotype) significantly more frequent in fistulizing and stenosing CD
Dresner-Pollak et al. [36]	2004	Israel, 228 CD (129 Ashkenazi and 99 non-Ashkenazi), 151 UC (72 Ashkenazi, 79 non-Ashkenazi), 495 HC (352 non-Ashkenazi and 143 Ashkenazi)	VDR: BsmI	BB genotype more frequent in Ashkenazi UC compared to Ashkenazi HC
Noble et al. [34]	2008	United Kingdom, 286 CD, 154 UC, 240 HC	VDR: TaqI, ApaI	Overall no differences between CD, UC, and HC for TaqI and ApaI. TaqI variants more frequent in male IBD patients compared to (male) HC
Naderi et al. [37]	2008	Iran, 150 UC, 80 CD, 150 HC	VDR: ApaI, TaqI, BsmI, FokI	FokI polymorphism significantly higher in UC and CD. Frequency of polymorphic “f” allele and f/f genotype higher in UC and CD comparing with HC
Pluskiewicz et al. [30]	2009	Poland, 47 UC, 47 HC	VDR: TaqI, BsmI, ApaI	No differences between UC and HC
Hughes et al. [29]	2011	Ireland, 660 IBD, 699 HC	VDR: ApaI, TaqI, BsmI, FokI	Borderline significance for heterozygous carriage of the FokI allele
Pei et al. [31]	2011	China, 218 UC, 251 HC	VDR: ApaI, TaqI, BsmI, FokI	Only Bb genotype of the BsmI variant associated with UC; frequency of the BsmI polymorphic allele (B) increased in UC
Eloranta et al. [42]	2011	Switzerland, 404 CD, 232 UC, 248 HC	DBP: rs 7041, rs 4588	Significantly reduced frequency of the 420 variant Lys in IBD compared to controls
Bentley et al. [35]	2011	New Zealand, 449 CD, 448 UC, 482 HC	VDR: FokI, TaqI	No overall differences, only a higher minor allele frequency for TaqI, in male CD and UC compared to HC
Luo et al. [33]	2013	China, 19 CD, 122 HC	VDR: ApaI, TaqI, BsmI	No significant differences in the frequencies of TaqI, BsmI, and ApaI polymorphisms
Xia et al. [32]	2014	China 382 UC, 489 HC	VDR: ApaI, TaqI, BsmI, FokI	No difference between UC and HC. The mutant allele C and genotype TC + CC of FokI were significantly increased in patients with mild and moderate UC compared to severe UC. The frequency of AAC haplotype was statistically lower in UC than HC (AAC haplotype formed by the VDR BsmI, ApaI, and TaqI gene might engender a reduced risk of UC attack)
Meta-analyses
Xue et al. [38]	2013	ApaI: 1024 CD, 974 UC, 1551 HC; FokI: 1187 CD, 1221 UC, 1746 HC; BsmI: 721 CD, 813 UC, 1642 HC; TaqI: 1568 CD, 1515 UC, 2152 HC	VDR: ApaI, TaqI, BsmI, FokI	FokI “ff” genotype associated with a significant risk for UC in Asians; TaqI “tt” genotype associated with an increased risk for CD in Europeans and with an increased risk for CD and UC in Asian males. ApaI “a” allele confers protection from CD
Wang et al. [39]	2014	ApaI: 940 CD, 962 UC, 1468 HC; FokI: 1098 CD, 1217 UC, 1676 HC; BsmI: 713 CD, 799 UC, 1616 HC; TaqI: 1553 CD, 1500 UC, 2145 HC	VDR: ApaI, TaqI, BsmI, FokI	ApaI, BsmI, and FokI are not significantly associated with IBD. Significant association between TaqI polymorphism and IBD risk.; In subgroups, ApaI increases the overall CD risk and BsmI increases this CD risk only in East Asians, whereas TaqI reduces the risk for UC especially in Caucasians

CD: Crohn’s disease; UC: ulcerative colitis; CRADC: cadaveric renal allograft donor controls; PCR: polymerase chain reaction; IBD: inflammatory bowel disease; HC: healthy controls; DBP: vitamin-D-binding protein; VDR: vitamin D receptor.
Article in Chinese.