Other strategies rely on genetic testing of the cancer compared to that of donor and recipient tissue (e.g. HLA typing). Different gene sequences and polymorphisms have been studied in the process of assessing imputability. Tumour origin can be identified by microsatellite analysis using Polymerase Chain Reaction (PCR). Paternity test by genomic allelotyping investigation is another reliable technique to verify imputability. This test permits the analysis of multiple highly polymorphic loci for effective discrimination of donor/recipient tumour origin. Many molecular tests can be performed on routinely processed paraffin-embedded tissue samples, and appropriate laboratory consultation is useful in assisting the clinician to take advantage of the local resources available to assess imputability.