The levels of TNF-α in the spinal cord of the animals inoculated with the preimmune goat IgG or with vehicle (group 0) were similar to those in the animals inoculated with the IgG from the normal human individual, from the Parkinson patient or from the patient with multifocal motor neuropathy (control group): 56 ± 12.78 pg/ml and 54.2 ± 8.12 pg/ml (means ± SD). This evidence concerns the gene TNF and Parkinson disease.