Winter 1 & 2 Exam 1 Guided notes
🧬 SECTION I: GENETICS & INHERITANCE
1️⃣ Single-Gene Disorders
Clinical Scenario:
You are ordering genetic testing for a child with a strong family history of
inherited disease.
🧠 Step 1: Define the Concept
Single-gene disorders occur when:
- The mutation affects one gene
- Mutation in one gene with clear inheritance
- Predictable
They follow what inheritance patterns?
☐ Autosomal dominant
☐ Autosomal recessive
☐ X-linked
☐ Multifactorial
✏️ Fill-In: Identify True Single-Gene Disorders
Examples include:
Sickle cell disease, cystic fibrosis, thalassemia, neurofibromatosis,
hemophilia, Duchene muscular dystrophy, fragile x syndrome,
polycystic kidney disease, Marfan’s syndrome, Tay Sach disease
Autosomal dominant: huntington and marfan
Seen in EVERY generation, does NOT skip
Affected parent = affected child
Autosomal recessive: cystic fibrosis and sickle cell disease
Skips generations
Parents are carriers
Shows up in siblings
X-linked: Duchenne muscular dystrophy and Hemophilia A
Mostly MALES affected
, Passed through carrier mothers
🔎 Clinical Reasoning Reflection
Why are Autism Spectrum Disorder and Down Syndrome NOT classified
strictly as single-gene disorders?
- ASD: polygenic + multifactorial, complex inheritance, no single
causative gene, affects many gene, not clearly autosomal dominant or
recessive d/t inconsistent inheritance pattern, environmental
contributions (prenatal factors, exposures)
- DS: chromosomal disorder (aneuploidy), extra copy of chromo 21, d/t
meiotic nondisjunction (not inherited mutation in a single gene), many
genes affected (gene dosage affect and genome-level abnormality)
2️⃣ Autosomal Dominant Inheritance (Huntington’s Disease)
Scenario: One parent has Huntington’s disease.
🧮 Risk Calculation
If one parent has an autosomal dominant disorder, each child has a:
__50____ % chance of inheriting the mutation.
Why?
- Gene mutation passed from one parent
- Only one copy needed to cause disease
- Passing either alle is random (like a coin flip)
Parent is usually heterozygous (Aa) and unaffected parent is (aa)
so if flip coin from affected parent and it lands on (A) then the child
is (Aa) because each parent gives one allele at random to the child –
so child is affected
(A)= mutation (a) = normal
🧠 Teaching Script (Fill-In Practice)
,“In autosomal dominant disorders, a child only needs ____1______ copy of the
mutated gene to develop the disease.”
⚠️ Clinical Pearl
Does Huntington’s skip generations? Why or why not?
- No because it is autosomal dominant and if one parent has the
mutation then each child has a 50% chance of developing it
👨👩👦 SECTION II: SHARED DECISION-MAKING & ETHICS
3️⃣ ADHD & Shared Decision-Making
Scenario: Parents hesitant about medication.
🧠 First Step in SDM:
What should you explore FIRST?
- Values, goals, and preferences
What matters most to them, beliefs, fears, expectations, health
literacy, decision style
List 3 open-ended questions you could ask:
1. “what are you most concerned about?”
2. “what matters most to you when making this decision?”
3. “how do you feel about these types of treatments?”
📊 Compare Treatment Options
Behavioral
/ Medication
Therapy
Medication
Pros:
- Faster symptom relief
- Helpful for moderate-severe symptoms
- Easy to administer
- Can be combined with therapy
- Faster symptom control
Cons:
- Side effects
- Does not address underlying behaviors alone
, - Risk is non-adherence or dependence
Behavior therapy
Pros:
- No medication side effects
- Addresses root behaviors/thought patterns
- Long term skill building
- Safe for children, pregnancy, polypharmacy patients
- Long term fix
Cons:
- Take time and effort to see results
- Requires patient motivation/compliance
- Access limited (cost + availability)
4️⃣ Vaccine Refusal
🧠 Best Initial Approach:
Write a strong recommendation statement:
“I strongly recommend __that you receive this vaccine today________ because
___it is safe, effective, and the best way to protect you from serious
disease_______.”
Recommend → Explore → Validate → Educate → Re-recommend → Respect
⚖️ Ethical Reflection:
Why is dismissing the family from care inappropriate?
1. Beneficence (do good)
Your duty is to promote the patient’s health
Dismissing them removes access to care → worsens outcomes
2. Nonmaleficence (do no harm)
Cutting off care can lead to:
o Missed diagnoses
o Delayed treatment
This creates preventable harm
🧬 SECTION I: GENETICS & INHERITANCE
1️⃣ Single-Gene Disorders
Clinical Scenario:
You are ordering genetic testing for a child with a strong family history of
inherited disease.
🧠 Step 1: Define the Concept
Single-gene disorders occur when:
- The mutation affects one gene
- Mutation in one gene with clear inheritance
- Predictable
They follow what inheritance patterns?
☐ Autosomal dominant
☐ Autosomal recessive
☐ X-linked
☐ Multifactorial
✏️ Fill-In: Identify True Single-Gene Disorders
Examples include:
Sickle cell disease, cystic fibrosis, thalassemia, neurofibromatosis,
hemophilia, Duchene muscular dystrophy, fragile x syndrome,
polycystic kidney disease, Marfan’s syndrome, Tay Sach disease
Autosomal dominant: huntington and marfan
Seen in EVERY generation, does NOT skip
Affected parent = affected child
Autosomal recessive: cystic fibrosis and sickle cell disease
Skips generations
Parents are carriers
Shows up in siblings
X-linked: Duchenne muscular dystrophy and Hemophilia A
Mostly MALES affected
, Passed through carrier mothers
🔎 Clinical Reasoning Reflection
Why are Autism Spectrum Disorder and Down Syndrome NOT classified
strictly as single-gene disorders?
- ASD: polygenic + multifactorial, complex inheritance, no single
causative gene, affects many gene, not clearly autosomal dominant or
recessive d/t inconsistent inheritance pattern, environmental
contributions (prenatal factors, exposures)
- DS: chromosomal disorder (aneuploidy), extra copy of chromo 21, d/t
meiotic nondisjunction (not inherited mutation in a single gene), many
genes affected (gene dosage affect and genome-level abnormality)
2️⃣ Autosomal Dominant Inheritance (Huntington’s Disease)
Scenario: One parent has Huntington’s disease.
🧮 Risk Calculation
If one parent has an autosomal dominant disorder, each child has a:
__50____ % chance of inheriting the mutation.
Why?
- Gene mutation passed from one parent
- Only one copy needed to cause disease
- Passing either alle is random (like a coin flip)
Parent is usually heterozygous (Aa) and unaffected parent is (aa)
so if flip coin from affected parent and it lands on (A) then the child
is (Aa) because each parent gives one allele at random to the child –
so child is affected
(A)= mutation (a) = normal
🧠 Teaching Script (Fill-In Practice)
,“In autosomal dominant disorders, a child only needs ____1______ copy of the
mutated gene to develop the disease.”
⚠️ Clinical Pearl
Does Huntington’s skip generations? Why or why not?
- No because it is autosomal dominant and if one parent has the
mutation then each child has a 50% chance of developing it
👨👩👦 SECTION II: SHARED DECISION-MAKING & ETHICS
3️⃣ ADHD & Shared Decision-Making
Scenario: Parents hesitant about medication.
🧠 First Step in SDM:
What should you explore FIRST?
- Values, goals, and preferences
What matters most to them, beliefs, fears, expectations, health
literacy, decision style
List 3 open-ended questions you could ask:
1. “what are you most concerned about?”
2. “what matters most to you when making this decision?”
3. “how do you feel about these types of treatments?”
📊 Compare Treatment Options
Behavioral
/ Medication
Therapy
Medication
Pros:
- Faster symptom relief
- Helpful for moderate-severe symptoms
- Easy to administer
- Can be combined with therapy
- Faster symptom control
Cons:
- Side effects
- Does not address underlying behaviors alone
, - Risk is non-adherence or dependence
Behavior therapy
Pros:
- No medication side effects
- Addresses root behaviors/thought patterns
- Long term skill building
- Safe for children, pregnancy, polypharmacy patients
- Long term fix
Cons:
- Take time and effort to see results
- Requires patient motivation/compliance
- Access limited (cost + availability)
4️⃣ Vaccine Refusal
🧠 Best Initial Approach:
Write a strong recommendation statement:
“I strongly recommend __that you receive this vaccine today________ because
___it is safe, effective, and the best way to protect you from serious
disease_______.”
Recommend → Explore → Validate → Educate → Re-recommend → Respect
⚖️ Ethical Reflection:
Why is dismissing the family from care inappropriate?
1. Beneficence (do good)
Your duty is to promote the patient’s health
Dismissing them removes access to care → worsens outcomes
2. Nonmaleficence (do no harm)
Cutting off care can lead to:
o Missed diagnoses
o Delayed treatment
This creates preventable harm
