HAM can further be standardized with respect to the selection of donors (e.g., exclusion of HIV-positive donors) and the testing of the material for infectious agents (e.g., agglutination tests for HIV (anti-HIV), HEP-C (anti-HCV), HEP-B (anti-HBc, HB-Ag), CMV (anti-CMV-IgG/-IgM), and TPHA- and ELISA-tests for syphilis and polymerase chain reaction tests for HIV, HCV, and HPV). The gene discussed is CD40LG; the disease is syphilis.