Final answer:
Huntington's disease is an autosomal dominant disorder, and cystic fibrosis is an autosomal recessive disorder, both resulting from single-gene defects. Genetic testing can identify carriers, and gene therapy is being explored as a treatment.
Step-by-step explanation:
Single-gene defects refer to genetic disorders that are caused by mutations in a single gene. Huntington's disease and cystic fibrosis are well-known examples. Individuals who have disorders due to single-gene defects often have distinct inheritance patterns. Huntington's disease is an example of an autosomal dominant disorder, where just one copy of the mutated gene is enough to cause the disease. This is in contrast to cystic fibrosis, which is an example of an autosomal recessive disorder, requiring two copies of the mutated gene to manifest in an individual.
Genetic testing can identify carriers of these genes, which is essential for informed family planning and early intervention. Scientists are exploring gene therapy to treat these kinds of genetic disorders by introducing the correct version of the gene to human cells.