Genetic studies in irritable bowel syndrome-status quo

Table 1 Number of articles, analyzing the relation between genetic polymorphisms and irritable bowel syndrome

Gene	SNP	Polymorphism	IBS type	Diagnostic criteria	Number of articles	Ref.
SLC6A4	rs4795541	5-HTTLPR (-1950- 1949insT, -1950-1949insC), STin2.9 VNTR	IBS-C	Rome I, II, III	15	[2-5,7-12,14,15,19,22,27]
	rs25531	179A > G (-1936A > G)		Rome II, III	4	[8-10,17]
HTR2A	rs6311	-1438G > A (-998G > A	IBS-D	Rome I, II, III	1	[4]
	rs6313	102C > T	IBS-D	Rome I, II, III	2	[4,35]
HTR3A	rs1062613	42C > T; 178C > T (-24C > T)	IBS-D	Rome I, II, III	6	[2,16,20-22,45]
HTR3E	rs56109847	76G > A	IBS-D	Rome I, II, III	5	[16,18,20,21,45]
GNB3	rs5443	825C > T	IBS-C	Rome II, III	8	[23-25,29,32,34,35]
TNFSF15	rs4263839	A/G	IBS-C	Rome I, II, III	3	[6,26,28]
Limited number of studies: pV158M CCK rec.intron1 NXPH1CDC42				Rome III	10	[30,31,33,36-40,43,44]

IBS: Irritable bowel syndrome; SNP: Single nucleotide polymorphisms.