The DICER1 gene, in the nucleus of a cell on chromosome 14, instructs cells how to make a protein called DICER1. This protein is an enzyme. DICER1 protein processes molecules to make microRNA (miRNA) which are very important controller molecules inside cells. Mutations in DICER1 gene have been discovered in some individuals and families with PPB and some of the diseases associated with PPB such as rhabdomyosarcoma and cystic nephroma. A mutation in DICER1 may be a part of the cause for these conditions in certain PPB patients and their families.