NACAD is a 1,562 amino acid protein that prevents non-secretory polypeptides from targeting the endoplasmic reticulum. Localizing to both the cytoplasm and nucleus, NACAD belongs to the NAC-alpha family and contains one NAC-A/B (NAC-alpha/beta) domain. The gene encoding NACAD maps to human chromosome 7, which houses over 1,000 genes and comprises nearly 5% of the human genome. Chromosome 7 has been linked to Osteogenesis imperfecta, Pendred syndrome, Lissencephaly, Citrullinemia and Shwachman-Diamond syndrome. The deletion of a portion of the q arm of chromosome 7 is associated with Williams-Beuren syndrome, a condition characterized by mild mental retardation, an unusual comfort and friendliness with strangers and an elfin appearance. Deletions of portions of the q arm of chromosome 7 are also seen in a number of myeloid disorders including cases of acute myelogenous leukemia and myelodysplasia.