GFI-1: ProductsGrowth Factor Independent Protein-1 (GFI-1) is a member of the zinc finger transcriptional regulator family of proteins. It is 422 amino acids (aa) in length and has a predicted molecular mass of 55 kDa. Mouse GFI-1 shares 79% aa sequence identity with the human protein. GFI-1 contains an N-terminal SNAG domain, an Ala/Gly-rich region, and six C2H2-type zinc finger motifs. It binds DNA at sequence-specific consensus sites and functions as a transcriptional repressor. GFI-1 is expressed by dendritic cells, granulocytes, hematopoietic stem cells, monocytes, macrophages, and T cells. It is required for hematopoietic stem cell self-renewal, neutrophil maturation, and regulates dendritic cell development and maturation. GFI-1 is also required for inner ear hair cell differentiation and loss of GFI-1 results in hearing loss. Mutation of GFI-1 results in severe congenital neutropenia, while single nucleotide polymorphisms or deletion of the GFI-1 gene are associated with acute myeloid leukemia.