Posttransplantation lymphoproliferative disorders frequently contain type A and not type B Epstein-Barr virus

have been defined on the basis of sequence divergence in the EBNA-2 gene. Type A EBV immortalizes B cells more efficiently in vitro and infects immunocompetent individuals more commonly than type B EBV. However, increased rates of infection by type B EBV are seen in immunocompromised hosts and in many lymphoid neoplasms associated with im-munocompromise. The posttransplantation lymphoprolifer-ative disorders (PT-LPDs) are a heterogeneous group of B-cell neoplasms that arise in the setting of immunosuppres-sive therapy, and are associated with EBV infection. Whether type A andlor type B EBV are associated with PT-LPDs is unknown. Therefore, we investigated 27 PT-LPD lesions from 22 solid-organ transplant recipients by polymerase chain reaction (PCR) at the EBNA-2 and EBNA-3c loci to de-ENOMIC ANALYSES of Epstein-Barr virus (EBV