Association of Fas/Apo1 gene promoter (-670 A/G) polymorphism in Tunisian patients with IBD

Table 1 Clinical characteristics of study subjects n (%)

	CD (n = 105)	UC (n = 59)
Sex (Male/female)	50/55	17/42
Age average	36.07	37.89
Age (Min/max)	23/60	25/74
Familial forms	9 (8.57)	4 (6.77)
Surgical history	11 (10.47)	4 (6.77)
Activity of the disease (n)	In remission (75)	In remission (46)
	Moderated (18)	Moderated (13)
	Severe (12)	Severe (0)
Location of lesion, (n)	Ileum (27)	Distal (21)
	Colon (24)	Left-sided colitis (26)
	Ileocolon (54)	Pancolitis (12)
Forms, n (%)	Stenosing, 43 (40.95)
	Fistula, 37 (35.23)
Extra-intestinal manifestation	31 (29.53)	5 (8.47)
Evolution, n (%)	Favorable, 89 (84.16)	Favorable, 58 (98.30)
	Cortico dependency, 12 (11.42)	Cortico dependency, 1 (1.69)
	Cortico-resistance, 2 (1.92)	Cortico-resistance, 0
	Unfavourable, 2 (1.92)	Unfavourable, 0
Production of pANCA	43	28
Production of ASCA	22	9
Treatments	5-ASA, 32 (30.47)	5-ASA, 58 (98.30)

Table 2 Allelic and genotypic frequency of (-670 A/G) Apo1/Fas gene polymorphisms in patients with inflammatory bowel disease and controls n (%)

ApoI/Fas (-670)	Controls (n = 100)	IBD (n = 164)	UC (n = 59)	CD (n = 105)
Genotypic frequencies
A/A	49 (49)	46 (28.04)c	15 (25.42)b	31 (29.52)a
A/G	32 (32)	70 (42.68)	30 (50.85)	40 (38.10)
G/G	19 (19)	48 (29.26)	14 (23.73)	34 (32.38)
Allelic frequencies
A	130 (70)e	162 (49.39)d	60 (50.84)f	102 (48.57)e
G	70 (35)	166 (50.61)	58 (49.16)	108 (51.43)

^aComparing AA genotype frequencies in CD patients with controls: P corrected = 0.004, OR: 0.44, 95% CI, 0.24 < OR < 0.81;

^bComparing AA genotype frequencies in UC patients with controls: P corrected = 0.0034, OR: 0.35, 95% CI, 0.16 < OR < 0.76;

^cComparing AA genotype frequencies in IBD patients with controls: P corrected = 0.0005, OR: 0.41, 95% CI, 0.23 < OR < 0.70;

^dComparing A/Allele frequencies in IBD patients with controls: P corrected = 0.0004, OR: 0.53, 95% CI, 0.36 < OR < 0.77;

^eComparing A/Allele frequencies in CD patients with controls: P corrected = 0.0007, OR: 0.57, 95% CI, 0.34 < OR < 0.77;

^fComparing A/Allele frequencies in UC patients with controls: P corrected = 0.01, OR: 0.56, 95% CI, 0.34 < OR < 0.91. IBD: Inflammatory bowel disease; UC: Ulcerative colitis; CD: Crohn’s disease; OR: Odds ratio; CI: Confidence interval.

Table 3 Incidence of (-670 A/G) Apo1/Fas gene polymorphism analyzed with respect to sex in IBD patients n (%)

ApoI/Fas	Controls (n = 100)	CD females (n = 55)	CD males (n = 50)	UC females (n = 42)	UC males (n = 17)
Genotypic frequencies
A/A	49 (49)	14 (25.45)a	17 (34)	12 (28.57)b	5 (29.41)
A/G	32 (32)	24 (43.64)	16 (32)	23 (54.76)c	7 (41.18)
G/G	19 (19)	17 (30.91)	17 (34)	7 (16.67)	5 (29.41)
Allelic frequencies
A	130 (70)	52 (47.27)	50 (50)	47 (55.95)	17 (50)
G	70 (35)	58 (52.73)	50 (50)	37 (44.05)	17 (50)

Fas genotypes were similar in controls of both sexes: 52 males and 48 females; χ² = 0.06, P = 0.8, two degrees of freedom;

^aχ² test of heterogeneity between CD females and controls (χ² = 8.15, two degrees of freedom, P corrected = 0.004) odds ratio for AA genotype is 0.36 (0.16 < OR < 0.77, CI = 95%);

^bχ² test of heterogeneity between UC females and controls (χ² = 5.04, two degrees of freedom, P corrected = 0.02) odds ratio for AA genotype is 0.42 (0.18 < OR < 0.96, CI = 95%);

^cχ² test of heterogeneity between UC females and controls (χ² = 6.46, two degrees of freedom, P corrected = 0.01) odds ratio for AG genotype is 2.57 (1.15 < OR < 5.76, CI = 95%).

Table 4 Association between (-670 A/G) Apo1/Fas gene polymorphism and location of lesion

ApoI/Fas	UC (n = 59)				CD (n = 105)
	G/G	G/A	A/A		G/G	G/A	A/A
Distal	4	9	8	Ileum	5	10	12a
Left-sided olitis	5	15	6	Colon	13b	8	3
Pancolitis	3	8	1	Ileocolon	16	22	16

^aχ² test between AA genotype and ileum location of lesion in CD patients (χ² = 3.89, two degrees of freedom, P corrected = 0.048) odds ratio is 2.48 (0.90 < OR < 6.87, CI = 95%);

^bχ² test between GG genotype and colon location of lesion in CD patients (χ² = 6.74, two degrees of freedom, P corrected = 0.009) odds ratio is 3.38 (1.19 < OR < 9.67, CI = 95%).