Summary of the frequency of polymerase chain reaction studies for the presence or absence of Mycobacterium paratuberculosis in Crohn's disease (CD), ulcerative colitis (UC), and non-inflammatory bowel disease (IBD) tissues. These are shown in order of date of publication
| Reference | Target | Non-IBD | UC | CD |
| Rosenburg et al 19918 | Not stated, not IS900 | 0/6 (0%) | nd | 0/21 (0%) |
| Wuet al 19919 | Pan mycobacterial sequences | nd | nd | 0/20 (0%) |
| Sandersonet al 199210 | IS900 | 5/40 (12.5%) | 1/23 (4.3%) | 26/40 (65%) |
| Dell'Isolaet al 199411 | IS900 | 7/24 (29%) | 1/5 (20%) | 13/18 (72%) |
| Lisby et al 199412 | IS900 | 3/28 (11%) | 2/10 (20%) | 11/24 (46%) |
| Fidler et al199413 | IS900. Also detected non M paratuberculosis sequences | 0/20 (0%) | 0/10 (0%) | 4/31 (13%) |
| Suenaga et al199514 | IS900 | 14/16 (87.5%) | 11/18 (61%) | 10/10 (100%) |
| GroEL | 14/16 (87.5%) | 11/18 (61%) | 10/10 (100%) | |
| Rowbotham et al199515 | IS900 | 1/26 (4%) | 0/49 (0%) | 0/68 (0%) |
| Murray et al199516 | IS900 | 0/15 (0%) | 2/15 (13%) | 2/9 (22%) |
| Kreuzpaintner et al199517 | 16S rRNA | 0/1 (0%) | nd | 0/4 (0%) |
| Culture | 0/23 (0%) | nd | 0/23 (0%) | |
| Erasmuset al 199518 | IS900 | 4/35 (11%) | nd | 10/26 (38%) |
| Mishina et al 199619 | IS900 mRNA | 0/2 (0%) | 4/4 (100%) | 8/8 (100%) |
| Frank and Cook 199620 | IS900 | 0/11 (0%) | nd | 0/23 (0%) |
| Dumonceau et al199621 | Mycobacteria | 13/23 (57%) | 6/13 (46%) | 17/36 (47%) |
| M paratuberculosis | 0/23 (0%) | 0/13 (0%) | 0/36 (0%) | |
| Dumonceau et al199722 | M paratuberculosis 16S rRNA | 0/22 (0%) | 0/10 (0%) | 0/31 (0%) |
| Al-Shamaliet al 199723 | IS900 | 0/21 (0%) | 0/6 (0%) | 0/10 (0%) |
| MP2 | 0/21 (0%) | 0/6 (0%) | 0/10 (0%) | |
| Riggio et al 199724 | IS900 | 0/12 (0%) | nd | 0/7 (0%) |
| Clarkston et al199825 | IS900 | 0/11 (0%) | 0/5 (0%) | 1/21 (5%) |
| Cellier et al199826 | 16S rRNA any mycobacteria | 2/20 (10%) | 1/27 (4%) | 2/47 (4%) |
| IS900 | 0/20 (0%) | 0/27 (0%) | 0/47 (0%) | |
| Chiba et al 199827 | IS900 | 0/3 (0%) | 0/14 (0%) | 0/30 (0%) |
| Kanazawa et al199928 | IS900 | 0/13 (0%) | 0/4 (0%) | 0/13 (0%) |
| Tiveljung et al199929 | 16S rRNA | 0/11 (0%) | nd | 3/11 (27%) |
| 1-150Ikonomopoulos et al200030 | IS1110 element and probed 16S rRNA | nd | 1/1 (100%) | 7/20 (35%) |
| 1-151Gibson et al200031 | IS900 | 0/12 (0%) | nd | 0/3 (0%) |