top of page

PUID: 42 || PLAB 2 Mock 5 :: CounselingCondition10: Huntingtons Disease



Summary:

This case revolves around a genetic counseling consultation for Huntington’s Disease (HD), an autosomal dominant neurodegenerative condition. The candidate is expected to explain the inheritance patterns, assess the patient's family history, and provide clarity on risks, testing, and reproductive options.



Key Points:


Genetics and Inheritance:

  • Huntington’s Disease (HD) is inherited in an autosomal dominant fashion.

  • A single copy of the defective gene (from one parent) is enough to cause the disease.

  • If one parent is heterozygous (Hh), the child has a 50% chance of inheriting the condition.

  • If the parent is homozygous dominant (HH), the inheritance risk increases to 100%.

  • Punnett squares are essential to illustrate inheritance risk clearly.

  • It's vital to collect a detailed family history up to the grandparents to assess genetic risk properly.


Pedigree Assessment:

  • Determine if the affected parent(s) are heterozygous or homozygous.

  • Ascertain history of HD in grandparents to help deduce the genetic status of the patient's parent.

  • Ask about both maternal and paternal sides for complete risk assessment.


Important Considerations:

  • HD symptoms worsen over generations (anticipation), typically appearing earlier in successive generations.

  • Affected individuals often show progressive movement disorders, psychiatric symptoms, and cognitive decline.

  • No cure exists, but symptom management can improve quality of life.

  • Be prepared for emotionally charged consultations.


Diagnostic Approach:

  1. Take a comprehensive family history, especially up to the grandparents.

  2. Assess clinical signs if any exist (though not always present in asymptomatic individuals).

  3. Refer to genetic counseling for further testing and evaluation.

  4. Consider genetic testing for confirmation (requires informed consent).


Management:

  • Refer to Clinical Genetics Service for testing and counseling.

  • Discuss possible outcomes and implications of testing.

  • Symptom Management: Include medications like antidepressants, antipsychotics, and movement disorder therapies.

  • Reproductive options:

    • Pre-implantation Genetic Diagnosis (PGD) with IVF

    • Prenatal testing during pregnancy

    • Adoption

  • Psychological Support: For anxiety, family impact, and future planning.

  • Provide written resources and schedule follow-ups for ongoing support.


Communication Skills:

  • Avoid medical jargon; explain concepts like genes, inheritance, and Punnett squares in layman's terms.

  • Use drawings to visually represent genetic risk.

  • Use empathetic and supportive language.

  • Confirm understanding throughout the explanation.

  • Validate patient concerns and allow space for emotional reactions.

  • Avoid overuse of rehearsed phrases; maintain natural conversation flow.


Ethical Considerations:

  • Respect the patient's right to make informed decisions about testing and reproductive choices.

  • Maintain confidentiality unless risk to others is identified and consent is given.

  • Avoid coercion or making assumptions based on lifestyle or beliefs.

  • Ensure patient autonomy is preserved in all decision-making processes.



Additional Resources:

  • GMC Guidance on good medical practice and patient communication.

  • GMC PLAB examiner tips on avoiding stock phrases, time management, and natural interaction.

  • Genetic counseling services via the NHS or referral pathway (check local availability).

  • Leaflets and support resources from Huntington’s Disease Association UK.

Comments

bottom of page