Final answer:
Trinucleotide expansion diseases include Huntington's disease, spinal muscular atrophy, and others, characterized by the lengthening of a trinucleotide sequence which can lead to various symptoms and are often hereditary.
Step-by-step explanation:
Trinucleotide expansion diseases are a group of genetic disorders caused by the lengthening of a specific trinucleotide sequence in DNA. The list of such diseases includes the following:
- Huntington's disease
- Certain forms of spinal muscular atrophy
- Fragile X syndrome
- Myotonic dystrophy
These diseases often worsen over generations and usually lead to a range of symptoms, depending on the affected genes and areas of the body.