BLOC1S2 (Biogenesis of lysosome-related organelles complex-1 subunit 2) protein is widely expressed in normal tissue as well as in malignant tumors with a tendency towards lower expression levels in certain subtypes of tumors. On the subcellular level, BLOC1S2 is expressed in an organellar-like pattern and co-localizes with mitochondria.

BLOC1S2, also known as BLOS2, belongs to the BLOC1S2 family. It is a component of BLOC-1 complex. The BLOC-1 complex is composed of BLOC1S1, BLOC1S2, BLOC1S3, DTNBP1, MUTED, PLDN, CNO/cappuccino and SNAPIN. The BLOC-1 complex is required for normal biogenesis of lysosome-related organelles, such as platelet dense granules and melanosomes. BLOC1S2 interacts directly with BLOC1S1, BLOC1S3, MUTED, CNO/cappuccino and SNAPIN. It may play a role in cell proliferation. It also plays a role in intracellular vesicle trafficking. Functionally, BLOC1S2 gene has been proposed to participate in processes (melanosome organization, microtubule nucleation, platelet dense granule organization, positive regulation of cell proliferation, positive regulation of transcription, regulation of apoptosis, positive regulation of transcription from RNA polymerase II promoter).

BACE2, also known as beta secretase 2, belongs to the peptidase A1 family. It is a protease known to be an important enzyme involved in the cellular pathways. BACE2 has been shown to interact with GGA1 and GGA2. It is the major β-secretase in vivo. BACE2 is located on chromosome 21 and may play a role in alzheimer's disease pathogenesis in down syndrome(DS). Overexpression of BACE2 by lentivirus markedly reduced amyloid β protein production in primary neurons. Despite an extra copy of the BACE2 gene in DS and the increase of its transcription, BACE2 protein levels are unchanged.