Huntingtons Disease An Overview HD Center of Excellence - PDF document

Huntington’s Disease An Overview HD Center of Excellence

Huntington’s Disease g Prevalence: 7 per 100,000 g Age of Onset: 2 - 82 y.; mean = 39; 10% onset < 20 y.; 25% onset > 50 y. g Duration of Illness: 3 - 50 y.; mean = 18 HD Center of Excellence

Genetically Inherited Disease g Autosomal dominant genetic disorder g Each child has a 50% chance of inheriting the genetic mutation for the disease g Males and females have an equal chance of inheriting the disease g Inherited equally across nationalities HD Center of Excellence

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Direct Gene Results g Normal CAG repeat length g < 30 g Intermediate CAG repeat length g gray zone under investigation g CAG repeat length in HD g > 39 range g Maternal Transmission g Paternal Transmission g Of 25 samples typed; all were g Of 37 samples typed; 19 within 2 CAG repeat lengths expanded from 3 to 50 CAG of parent repeat lengths HD Center of Excellence

Age at onset by CAG repeat size 90 80 Age at Onset (years) 70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 70 80 90 100 110 120 130 CAG Repeat Size HD Center of Excellence

The Decision to Test... g WFN, IHA, HDSA Guidelines for the Ethical Conduct of Genetic Testing g Impact on employment and insurance g Impact on psychosocial: less well adjusted were positive, married, no children, and closer to age of onset HD Center of Excellence

Clinical Triad of Symptoms in HD Psych. M otor HD Center of Excellence Cognitive

What Do We Know About Behavior and the Brain? g Our behavior is directly affected by changes in the brain g Day-to-day effects on brain: fatigue and stress g Chronic effects on brain: disease g Compensatory aspects of the brain g We see behavior changes before diagnosis HD Center of Excellence

Behavior and the Brain HD Center of Excellence

Circuits in the Brain HD Center of Excellence

Filtering, organizing, prioritizing HD Center of Excellence

Planning & Organization HD Center of Excellence

“Gates” in the Brain HD Center of Excellence

What Happens When Gates Fall Out of Repair? g Poor control of temper g Poor control of recall g Dysregulation of emotion and thinking g Confusion HD Center of Excellence

Need for Presymptomatic Treatment g By the time of diagnosis: � Many patients (or family members) have noticed difficulty in thinking skills, reasoning, and emotional changes such as anger or depression g Therefore: to be most effective, many new treatments under study aim to prevent symptom onset. g Detailed discussion at afternoon session. HD Center of Excellence