Final answer:
Genome-wide association studies are used to investigate a broad spectrum of noninfectious diseases that have genetic or environmental foundations, including genetic disorders, autoimmune diseases, and complex conditions influenced by multiple factors.
Step-by-step explanation:
Genome-wide Association Studies (GWAS)
Genome-wide association studies are used to study a variety of noninfectious diseases that have genetic or environmental factors as their cause, rather than infectious agents like viruses or bacteria. These include but are not limited to genetic disorders, autoimmune diseases, and diseases influenced by multiple genes and environmental factors. For example, cystic fibrosis, most cancers, cardiovascular diseases such as coronary artery disease, and diabetes mellitus are all noninfectious diseases that may be studied with GWAS. GWAS can shed light on diseases like agammaglobulinemia, which is a genetic condition leading to the lack of production of antibodies, and autoimmune diseases of the heart like rheumatic fever.
The difficulty in identifying the causes of many nervous system disorders lies in the complexity of genetic associations, lack of obvious brain structure defects, and the variable onset and display of symptoms between patients.
Furthermore, gene therapy can involve the introduction of foreign DNA into cells not just for molecular cloning or PCR, but also for the treatment of inheritable diseases, making it a versatile tool in the fight against various genetic ailments.