We have analyzed approximately 70 kb of the chromosome 14q11.2 hematopoietic serine protease gene cluster for the presence of nuclear scaffold attachment regions (SARs). At least 12 potential attachment sites were identified. SARs are present on both sides of the CGL-1/CSP- B and CGL-2/CCP-X genes and upstream from the cathepsin G (CG) gene. We have further characterized the SARs immediately flanking the cytotoxic lymphocyte-specific CGL-1/CSP-B gene. These 5′ and 3′ SARs are highly A- T-rich, contain multiple attachment sites, and are associated with the scaffolds of nuclei derived from both lymphoid and erythroid cell lines. These SARs contain multiple consensus elements frequently associated with A-T-rich sequences, including the vertebrate topoisomerase II (topo II) consensus sequence, the A-box and T-box elements, and the yeast autonomous replicating sequence (ARS). The potential role for the nuclear scaffold in the transcriptional regulation of CGL-1/CSP-B expression is discussed.