How can protein cause a disease?

Proteins can cause diseases when they misfold or aggregate, leading to dysfunctional cellular processes. Misfolded proteins may form toxic aggregates, as seen in neurodegenerative conditions like Alzheimer's and Parkinson's disease. Additionally, certain proteins can trigger autoimmune responses, where the immune system mistakenly attacks the body's own tissues. Genetic mutations can also result in abnormal protein function, contributing to various inherited disorders.