Which of the following conditions is classified as an autosomal dominant disorder?

Huntington's disease is classified as an autosomal dominant disorder due to its inheritance pattern, which means that only one copy of the mutated gene from an affected parent is sufficient to cause the disorder in their offspring. This genetic condition is caused by a defect in the HTT gene located on chromosome 4, leading to neurodegenerative symptoms that typically manifest in middle adulthood.

In the context of genetic disorders, autosomal dominant conditions display the trait in individuals who inherit just one copy of the mutated allele. The offspring of an affected individual have a 50% chance of inheriting the condition. This is in contrast to the other conditions listed, which follow different inheritance patterns, such as autosomal recessive (like Cystic Fibrosis and Thalassemia) or chromosomal abnormalities (like Down Syndrome). Understanding these inheritance patterns is crucial for recognizing how different genetic conditions are passed down through families.