Clue 1: Orient yourself
What stays identical in both machines?
Use the labels and the picture's left-to-right, near-to-far, or before-and-after order. Name only what you can point to.
The question
Why do most kids with a cleft carry no broken instruction at all?
Why it matters: Genetic results can change family counseling and research decisions. They must be interpreted without turning risk into destiny or an uncertain variant into a diagnosis. Today you practice the professional reasoning behind that work: A regulatory variant changes when or how much a gene is used without changing the protein sequence.
On your WebXam
Distinguishing a regulatory risk allele from a protein-coding mutation
For life
Turn the amount up and down; the result tells you if the signal decides or just allows.
Principle: Boss or doorman?
Five principles we return to
Having it is not using it
Same instructions, different switches
Same look, different cause
Change one thing and watch
Boss or doorman?
Decides the result or only allows it
Held down, not gone
Remove the brake and it returns
Many roads, one ending
One result can begin many ways
Try the everyday version first
The machine is intact, but its dimmer switch changes output
A dimmer changes how strongly a working light operates. The bulb and wires can remain present while the amount of light changes.
Do not jump to the biology yet. Treat the picture as a small system. Track its parts, follow one change at a time, and keep more than one explanation open until the picture supplies a way to separate them.
Clue 2: Trace one change
Which control changes the amount produced?
Follow one object, stage, or path. Point to the first place where the situation changes instead of jumping to the ending.
Clue 3: Keep the cause open
Why would output depend on the room and time?
List more than one explanation that still fits. Name the extra observation that would help you separate those possibilities.
Now inspect the illustration
Work from the visible evidence. A useful answer names the part of the picture that supports it and leaves unknown causes open.
- 1What stays identical in both machines?
- 2Which control changes the amount produced?
- 3Why would output depend on the room and time?
Tier 1 check
Finish with the everyday model
Use the everyday picture to answer today's question in plain words: Why do most kids with a cleft carry no broken instruction at all?
You can complete today's required check without opening the technical details below.
Ready for the real names? Optional tier 2
Technical rules and limits
Rule 1: The instructions and their controls are separate.
Rule 2: Controls change when and where instructions are used.
Rule 3: A risk marker changes probability rather than guaranteeing disease.
Where the analogy stops: Enhancers integrate many factors and are not single household dimmers.
Carry the previous idea forward
Variant location can change mechanism: reduced dosage and altered DNA binding can produce different IRF6-related outcomes.
Today's technical takeaway
A regulatory variant changes when or how much a gene is used without changing the protein sequence.
Now map the same rules onto biology
Map rs642961 to an IRF6 enhancer
Machine
IRF6 protein coding sequence
Dimmer
IRF6 enhancer
Lower output
Changed gene expression during facial development
Educational illustration, not a clinical photograph or diagnostic result. Use the labeled evidence cards and claim ceiling.
Mateo's case file: evidence supplied in this lesson
GEN09-E1
rs642961 lies in an IRF6 enhancer rather than a protein-coding exon.
Why it matters: The variant does not change an IRF6 amino acid.
GEN09-E2
The risk allele disrupts an AP-2alpha binding site in laboratory assays.
Why it matters: A molecular regulatory mechanism is supported.
GEN09-E3
The allele is associated with increased cleft-lip risk but is found in unaffected people.
Why it matters: It is a risk allele, not a deterministic syndrome mutation.
Make the clinical decision
You are reviewing an isolated-cleft research result.
A report finds one rs642961 risk allele and no pathogenic coding variant.
ADescribe a modest regulatory risk contribution, not a diagnosis.
BCall it a guaranteed cause.
CDismiss it because the protein sequence is unchanged.
Choose the interpretation and cite regulatory mechanism plus penetrance.
Evidence required
GEN09-E1 + GEN09-E2 Claim ceiling
You may describe association and mechanism. You may not claim the allele alone caused Mateo's cleft.Go deeper Optional tier 3
Everything required for today is above. Open these only if you want the explainer, source trail, or download files.
The everyday model and Tier 1 check are the complete required path for this lesson.
Use these checks to keep your place. They are not turned in through the portal.
Check off as you finish
- Worked through the everyday picture and answered its three questions.
- Completed the Tier 1 check in plain words.
Turn in: Genetics lesson 9: The Hidden Regulatory Variant
Go to Schoology to turn this in.
Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf.
Open Schoology PDF upload helpIf you cannot get in, see Mr. Mendoza. Do not skip the work.
Optional legacy technical materials Open only if you want the original notes, vocabulary, artifact, and CER work
Before this page, you should know
- IRF6 has a (residues 7 to 115) and a ; changes are enriched in the DNA-binding domain but not the protein-binding domain.
- Truncating typos (/) spread across the gene cause through (half-dose).
If not, review
Today's new idea is only
The same gene can cause disease two ways: rare coding changes break the and cause syndromes, while a common regulatory change lowers how much protein is made and nudges up -lip risk.
Goal: Students will distinguish coding from regulatory variants and explain how the common -lip risk variant rs642961 raises risk by disrupting an AP-2alpha instead of changing the .
Know by the end
- A changes the sequence; a changes a control region and alters how much protein is made, without changing the sequence.
- IRF6 has an called MCS-9.7 about 10 kb where the AP-2alpha (TFAP2A) normally docks to switch IRF6 on.
- The common variant rs642961 (G to A) sits inside MCS-9.7; the A does not change the IRF6 but blocks AP-2alpha binding, dialing IRF6 down in lip-forming .
- rs642961 is specific to lip, has a modest around 2, and accounts for about 18% of -lip risk in the studied populations.
1
Two locations for a variant
Model start: A changes the sequence; a changes a control region and alters how much protein is made.
- A changes the ____ itself (the and typos from earlier lessons).
- A changes a control region, like an ____, and alters HOW MUCH is made, without changing the sequence.
2
The rs642961 switch
- rs642961 lies in the IRF6 MCS-9.7 about 10 kb ; the (A) disrupts a docking site for the AP-2____.
- So the factor cannot bind and IRF6 is turned down in lip-forming , without changing the IRF6 .
3
Why this links back to Mateo
- Rare coding changes ____ the and cause syndromes; a common regulatory change lowers the protein ____ and nudges up risk of ordinary lip.
- Mateo's is isolated and multifactorial, so a common small-effect regulatory like rs642961 fits his picture, not a rare syndrome .
Everything you need for today is on this page. These links are optional.
What to read
Read the short plain-language explanation written for this lesson. Plain-language explainer for this lesson
Why this source matters
This explanation gives you the background for today's idea without making you decode a research paper: The same gene can cause disease two ways: rare coding changes break the and cause syndromes, while a common regulatory change lowers how much protein is made and nudges up -lip risk.
Words to unlock first
Reading moves
- 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.
Stop point
Stop after the final 'Use it now' section. The research citations are available separately for advanced readers.
Your output
Write one claim-evidence sentence: state the main idea, then name the example or evidence that supports it.
Where this fits
Tested on (Ohio WebXam)
Genetics of Disease · 072130
PLTW lesson
MI · Genetics domain · Unit 2 How to Screen Your Genes, 2.2 Our Genetic Future
WebXam domain
Molecular and Genetic Technology
Evidence to produce
In the genetic counselor's note, write two sentences for the family: one explaining that rs642961 does NOT change the IRF6 protein but turns it down by breaking a switch, and one stating why it is a risk factor, not a guaranteed cause.
Lab / skill
Medical Interventions (MI) · Principles of Biomedical Science (PBS)
Everything required for today's decision is already in the case file and plain-language explainer. The links below are original papers and database records for teachers and advanced readers, not assigned student reading.
- Claim: rs642961 raises risk even though it does not change the IRF6 ____.
- Evidence: The A sits in the MCS-9.7 ____ and, in a binding test, blocks ____ from docking.
- Reasoning: Therefore a can cause disease by ____, which shows that not all important variants are in the code.
How this is graded (rubric)
For: In the genetic counselor's note, write two sentences for the family: one explaining that rs642961 does NOT change the IRF6 protein but turns it down by breaking a switch, and one stating why it is a risk factor, not a guaranteed cause.
| 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 through the route named under Submit here and confirmed. | Turned in, but in the wrong place or unconfirmed. | Not turned in. |
How the model answer scores against this rubric
- CompleteProficient: Nothing is left blank: the model fills every part of "In the genetic counselor's note, write two sentences for the family: one explaining that rs642961 does NOT change the IRF6 protein but turns it down by breaking a switch, and one stating why it is a risk factor, not a guaranteed cause.".
- 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 attached to your class form or handed in, and confirmed.
What's next: A lowers how MUCH IRF6 is made, while syndromic variants damage specific parts. To understand both, we need to see the protein itself. What does the IRF6 protein actually look like?