The BC200 RNA is the product of an unprocessed monomeric Alu sequence. It is 200 nucleotides long and non-translatable.
BC200 has three distinct structural domains. The 5 region of the RNA defines one domain and consists of Alu repeat elements. The other two structural domains are a central A-rich region, and a C-rich 3 region specific to BC200. The 5 end of this molecule has both primary and secondary structure that is very similar to 7SL RNA, a signal recognition particle RNA (SRP) which also includes a 5 Alu domain.
The BC200 RNA gene has two pseudogenes: BC200 beta and BC200 gamma. These two pseudogenes each have a single gene in the genome, located on separate chromosomes. The beta pseudogene is composed of a BC200 RNA gene and additional Alu sequences. The gamma pseudogene contains an inverted long interspersed nuclear element (LINE). They both have transpositional ability, but the exact mechanism is unknown.