Table 1.

Position and diversity of variable regions of the SSU rRNA gene extracted based on the SSU rRNA gene sequence of 1140 human gastrointestinal phylotypes.

Variable region	Starting and ending positions (E. coli)	Reference	Number of sequences	Number of distinct sequences	Percentage of distinct sequences
V1	65–104	Bertilsson et al. (2002)	849	743	87.51
V2	174–235	Lane (1991)	875	759	86.74
V3	442–492	Lane (1991); Hugenholtz et al. (1998)	1107	687	62.06
V4	705–763	Hugenholtz et al. (1998)	1002	556	55.49
V5	822–879	Lane (1991); Hugenholtz et al. (1998)	988	682	69.03
V6	985–1047	Heuer et al. (1999)	895	754	84.25
V7	1115–1175	Roest (2007)	874	635	72.65
V8	1253–1313	Nübel et al. (1996)	865	699	80.81
V9	1420–1481	Lane (1991)	446	365	81.84