Similar Presence of B1 Repeats in 200and 300-Base Stretches in the 3-UTR of cDNAs from Subtracted/Normalized and Control Cap-Trapper cDNA Libraries
| Library | Normalized-subtracted sublibrary | Control sublibrary |
| Embryo 18 | 1.3% (143/10970) | 1.6% (4/244) |
| Stomach | 1.3% (114/8840) | 0.6% (10/1606) |
| Tongue | 1.2% (131/10974) | 0.7% (10/1408) |
| ES cells | 1.4% (209/15220) | 0.9% (10/1089) |
| Embryo 13-liver | 0.7% (37/5521) | 1.0% (7/718) |
| Embryo 10 | 1.8% (225/12724) | 1.3% (30/2239) |
| Embryo 12-head | 1.8% (160/8873) | 1.4% (7/490) |
[i] The number of clones positive for B1 sequences versus the total number of sequences analyzed is indicated in parentheses.