Gene Polymorphisms in Chronic Periodontitis

Table 7

IL6 and IL6R gene polymorphisms and carriage of the Rare (R)-allele in case-control studies and association with susceptibility to chronic periodontitis.

		Patients		Controls
IL6 gene	Ethnicity	n	R-allele	n	R-allele	Associated	Reference
polymorphism	of subjects		carriage		carriage	with periodontitis
−174 G>C	Caucasian	148	77%	107	84%	−	Holla et al. 2004 [57]
	Caucasian	57	61%	100	44%	+	Brett et al. 2005 [10]
	Caucasian	124	42%	116	28%	+^2	Babel et al. 2006 [58]
	Caucasian	137	65%	82	62%	−	Wohlfahrt et al. 2006 [59]
	Caucasian	51	78%	178	79%	−	Tervonen et al. 2007 [13]
	Caucasian	326	61%	144	71%	+^3
	Afro-American	93	10%	45	16%	−	Nibali et al. 2009 [60]
	Asian	87	20%	29	24%	−
	Brazilian	48	37%	36	67%	+^4	Trevilatto et al. 2003 [61]
	Japanese	112	0%	77	0%	−	Komatsu et al. 2005 [62]
	Brazilian	1551	44%	54	37%	−	Moreira et al. 2007 [63]
−190 C>T	Japanese	112	0%	77	0%	−	Komatsu et al. 2005 [62]
−572 C>G	Caucasian	148	6%	107	20%	+^4	Holla et al. 2004 [57]
	Japanese	112	37%	77	47%	−	Komatsu et al. 2005 [62]
	Caucasian	326	10%	144	8%	−
	Afro-American	93	21%	45	13%	−	Nibali et al. 2009 [60]
	Asian	87	61%	29	55%	−
−373	Japanese	112	12%	77	21%	+^5	Komatsu et al. 2005 [62]
(A(n)T(m)			(A9T11)		(A9T11)
−597 G>A	Caucasian	148	78%	107	84%	−	Holla et al. 2004 [57]
	Japanese	112	0%	77	0%	−	Komatsu et al. 2005 [62]
−1363 G>T	Caucasian	326	14%	144	22%	+
	Afro-American	93	1%	45	4%	−	Nibali et al. 2009 [60]
	Asian	87	5%	29	14%	−
−1480 C>G	Caucasian	326	58%	144	56%	−
	Afro-American	93	8%	45	16%	−	Nibali et al. 2009 [60]
	Asian	87	19%	29	24%	−
−6106 A>T	Caucasian	326	38%	144	37%	−
	Afro-American	93	36%	45	38%	−	Nibali et al. 2009 [60]
	Asian	87	38%	29	48%	−
R +48892 A>C	Japanese	169	66%	70	66%	− (+^6)	Galicia et al. 2006 [64]
R −183 G>A	Japanese	169	76%	70	74%	−	Galicia et al. 2006 [64]

nr = not reported. − = association not found. + = association found.
1Cases diagnosed as mixed periodontitis status.
2Only R/R genotype frequency is reported and is associated with CP
3IL-6 −174, −1363, and −1480 haplotype is associated with periodontitis.
4N/N genotype is associated with CP.
5Carriage rate of the −373 A9T11 allele higher in non-CP.
6N-allele is associated with CP.