TDP-43, a newly described neurodegenerative protein, is of great interest to both neurologists and geneticists. At the beginning, its dysfunction was recognized in sporadic amyotrophic lateral sclerosis, frontotemporal lobar degeneration with ubiquitinated inclusions and in mixed forms. However, it was also proved that TDP-43 inclusions are in addition present in many other diseases, for example in inclusion body myositis. Furthermore, many genes and different loci may be involved in pathological TDP-43 accumulation in cells and tissues. Mutations in the TARDPB gene, progranulin gene (PGRNVCP) as well as a gene on chromosome 9p were found. The present paper is a summary on possible involvement of TDP-43 in various neurodegenerative disorders.