How Do We Prove the Gene Causes It?
Take the reading one piece at a time. For each piece: read it once, underline the sentence that says what happens, then look up any word in the list. Tap a word to see its definition.
Piece 1 of 2
Scientists make a knockout, an animal with a gene deliberately switched off, and compare it to a normal wild-type animal. For IRF6 the results line up across two species. A wild-type mouse differentiates its periderm, fuses its palate, and lives; an Irf6-knockout mouse fails to form periderm, develops a cleft palate with oral and skin adhesions, and dies perinatally. A wild-type zebrafish has a normal anterior neurocranium (the fish primary-palate analog) and mouth; an irf6-knockout zebrafish has a cleft of the anterior neurocranium and a cleft-like mouth, with the downstream target esrp1 dropping about 80%. The same gene, knocked out in a mouse and in a fish whose ancestor we shared long ago, produces a cleft in both.
Piece 2 of 2
The closing argument is the rescue experiment: put the gene back and see if the cleft goes away. In zebrafish, injecting normal irf6 mRNA into irf6-null embryos restored esrp1 and rescued the cleft. In mouse, re-expressing Irf6 partially rescued: the pups survived and skin adhesions resolved, though the cleft palate persisted because IRF6 was not restored in the periderm cells themselves.
Reading the Research
- Skim the title and abstract first to get the gist.
- Circle the one sentence that states the main claim.
- Box the evidence the authors give for that claim.
- Mark one sentence that confuses you, and move on.
Now put it together: In one or two sentences, say what this whole reading is telling you about Mateo. Then go back to the lesson and fill in the guided notes.