Can We Fix the Code?
Can we fix the genetic code behind a , and if so, how far along is that work, really?
💡 Several molecular strategies correct clefting in animals, but every one is : there is no human or for CL/P, which is still managed by surgery and team care.
Prerequisite check
- is the chance a future child is affected given the family already has an affected child.
- For nonsyndromic, multifactorial CL/P, counselors use measured from real families (about 2.5% after one , about 4.6% after CLP), not a Punnett square.
What you will learn
Goal: Describe three molecular strategies to correct or compensate for a clefting gene defect, and explain clearly that every one is with no human therapy in use.
- treats disease by adding, correcting, or adjusting genes or their products.
- nudges a pathway up or down without rewriting DNA; a Wnt agonist rescued Pax9-null mouse palates in utero.
- or mRNA add-back supplies the missing product; recombinant TGF-beta-3 rescued ex vivo, and irf6 mRNA restored esrp1 in zebrafish.
- Every strategy is (animal or ex vivo); a edit changes only the patient and is not inherited, while a edit changes , egg, or sperm and is inherited.
Model: Three real laboratory strategies, and the vocabulary that decides everything
Three published results show different ways to correct a clefting defect, all in models. Gene-dosage or pathway modulation: giving pregnant mice a small-molecule Wnt agonist (a Dkk inhibitor) to compensate for Pax9 loss made the palatal shelves grow and fuse in utero, a in-animal result. replacement: adding recombinant TGF-beta-3 protein to grown in a dish made shelves that could not fuse, fuse, a preclinical ex-vivo result. Gene or mRNA add-back: putting an Irf6 transgene into mice and injecting irf6 mRNA into zebrafish gave a partial rescue, with survival and skin improved in mice (cleft palate persisted) and the target esrp1 restored in fish.
Two distinctions tell you what each result really means. means tested in animals or in a dish; clinical means tested in humans. Every strategy here is preclinical, and there is no clinical for human CL/P in the literature. A edit changes only the patient's own body cells and is not inherited; a edit changes egg, sperm, or cells and is passed to future generations. No somatic gene therapy and no germline gene editing for human CL/P exists.
Explore (work the model before reading on)
- List the or system used in each of the three strategies.
- Which result is a full rescue and which is only a partial rescue?
- Every Stage entry says . What is the single most important thing this tells a patient's family right now?
- The Wnt-agonist rescue had to be given to a pregnant mouse, in utero, during a short window. Why does the timing of make a human version especially hard?
- Suppose a future team could safely correct IRF6 in a single patient's cells without touching egg or sperm. Which label applies, or , and why does that label matter ethically?
Guided notes
Three approaches, all in models
- -style correction would rewrite a faulty DNA letter back to normal; for CL/P this remains a ____, not a published cure.
- does not rewrite DNA at all; it nudges a pathway up or down, like the ____ agonist that rescued Pax9-null palates in utero.
- or mRNA add-back supplies the missing product, like recombinant ____ rescuing ex vivo.
The honest headline and the two labels
- Every genetic or molecular fix for CL/P to date is ____ (animal or ex-vivo proof of concept); human CL/P is still managed by surgery and a team.
- A ____ edit changes only the patient and is not inherited.
- A ____ edit changes , egg, or sperm and is passed to all future generations, which is why it is far more tightly restricted.
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.
Vetted readings for this lesson
- Jia et al. 2017, Wnt agonists correct cleft palates in Pax9 mutant mice in utero (Development)
- Taya et al. 1999, Pathogenesis of cleft palate in Tgfb3 knockout, ex-vivo rescue (Development)
- Kousa et al. 2017, IRF6 partial rescue in Irf6 knockout mice (Dev Dyn)
- Babai & Irving 2023, Orofacial Clefts: management of CL/P (Genes)
Track your progress today
Check these off as you work through the lesson, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
- Read the Model and answered the Explore questions.
- Filled in the guided notes in my own words.
- Defined the new vocabulary with an example.
- Built the producible: Write one honest paragraph for a family who read online that "gene therapy can fix cleft lip." In four to five sentences: name the most promising real strategy and its model, state plainly that it is preclinical and not available for humans, and name the central practical obstacle (the short in-utero fusion window). Do not overpromise.
- Wrote my Claim, Evidence, and Reasoning exit ticket.
Exit ticket (Claim, Evidence, Reasoning)
- Claim: State whether a molecular cure for human lip and exists today.
- Evidence: Cite one result and the model it used, for example the ____ agonist rescuing Pax9-null palates in mice.
- Reasoning: Explain the difference between worked in a ____ and available for a human patient.
| Criterion | Proficient | Developing | Beginning |
|---|---|---|---|
| Complete | Every required part of the artifact is present and filled in. | Most parts are present, but one is missing or left blank. | Several parts are missing. |
| Accurate | The science and data are correct and match the evidence. | Mostly correct, with a small factual slip. | Key science or data is wrong. |
| Scientific reasoning (CER) | States a claim, backs it with specific evidence, and explains the reasoning. | Has a claim and evidence, but the reasoning is thin or missing. | Gives an answer with no evidence or reasoning. |
| Professional communication | Clear, organized, and labeled the way a clinician or scientist would write it. | Readable but disorganized or missing labels. | Hard to follow. |
| Submitted | Turned in the right way (Schoology for routine work) and confirmed. | Turned in, but in the wrong place or unconfirmed. | Not turned in. |
- CompleteProficient: Nothing is left blank: the model fills every part of "Write one honest paragraph for a family who read online that "gene therapy can fix cleft lip." In four to five sentences: name the most promising real strategy and its model, state plainly that it is preclinical and not available for humans, and name the central practical obstacle (the short in-utero fusion window). Do not overpromise.".
- AccurateProficient: Every number and claim matches the case evidence.
- Scientific reasoning (CER)Proficient: It names a claim, cites the specific evidence, and explains the reasoning, not just the answer.
- Professional communicationProficient: It is organized and labeled like a real chart note.
- SubmittedProficient: It would be turned in on Schoology and confirmed.
Where this leads: careers
What's next: These fixes work in animals today, and the science is moving. That raises a question no experiment can answer: if correcting a gene in a human ever became possible, should we do it, and who gets to decide? We chase that next.