This gene encodes the beta subunit of complement component C8 that participates in the assembly of the complement membrane attack complex. The encoded preproprotein undergoes proteolytic processing to generate the beta subunit, which associates with the alpha and gamma subunits to form a trimeric complement component, C8. Alternative splicing results in multiple transcript variants encoding different isoforms that may undergo similar proteolytic processing. This gene is located adjacent to the gene encoding the alpha subunit. [provided by RefSeq, Oct 2015]