The accumulation of protein called amyloid `beta` peptide in human brain causes:

Options

A. Addison’s disease
B. Huntington’s disease
C. Parkinson’s disease
D. Alzheimer’disease

Answer

To solve the question regarding the accumulation of protein called amyloid beta peptide in the human brain, we need to analyze the options provided and identify which condition is associated with this accumulation.

### Step-by-Step Solution:

1. **Understanding Amyloid Beta Peptide**:
- Amyloid beta peptide is a protein that is associated with the development of certain neurodegenerative diseases. Its accumulation in the brain is a significant factor in the pathology of these diseases.

2. **Evaluating the Options**:
- **Option A: Addison Disease**:
- This disease is related to insufficient production of hormones (cortisol and aldosterone) from the adrenal cortex. It does not involve amyloid beta peptide or brain function.
- **Conclusion**: Incorrect option.

- **Option B: Huntington Disease**:
- Huntington's disease is an autosomal dominant disorder caused by a mutation in the HTT gene. It is characterized by movement disorders and cognitive decline but is not related to amyloid beta peptide accumulation.
- **Conclusion**: Incorrect option.

- **Option C: Parkinson Disease**:
- Parkinson's disease is primarily a movement disorder caused by the degeneration of dopamine-producing neurons in the brain. It does not involve amyloid beta peptide accumulation.
- **Conclusion**: Incorrect option.

- **Option D: Alzheimer Disease**:
- Alzheimer’s disease is characterized by severe memory loss and dementia. It is directly associated with the accumulation of amyloid beta peptide in the brain, which leads to neurodegeneration and cognitive decline.
- **Conclusion**: Correct option.

3. **Final Answer**:
- The accumulation of protein called amyloid beta peptide in the human brain causes **Alzheimer disease**.