Garth A. Nicholson mostly deals with Genetics, Amyotrophic lateral sclerosis, Mutation, Gene and Missense mutation. Garth A. Nicholson has included themes like C9orf72, Frontotemporal dementia, Genome-wide association study and RNA-Binding Protein FUS in his Amyotrophic lateral sclerosis study. His work deals with themes such as C9orf72 Protein and TARDBP, which intersect with C9orf72.

He works mostly in the field of TARDBP, limiting it down to topics relating to TAR DNA-Binding Protein 43 and, in certain cases, Neurodegeneration. The Mutation study combines topics in areas such as Molecular biology and Glycine—tRNA ligase. His work in Gene addresses issues such as DNA, which are connected to fields such as RNA and Juvenile amyotrophic lateral sclerosis.