Living donor liver transplantation (LDLT) was conceived as a way to increase the availability of donated organs, and was initiated in infants and children more than 2 decades ago. The Hume-Lee Liver transplant program and its directors have actively enrolled adult living liver donors and their adult liver recipients contributing significantly to all eight research aims of the adult to adult living donor liver transplant study (A2ALL) 1U01DK062531-01, awarded to Virginia Commonwealth University (VCU) on 09/17/2002. Over seven years and three phases of study in A2ALL, VCU has contributed 11% (198 of 1750 patients) of the total study patient population and 10% (108 of 1049 patients) of the prospective cohort era study patient population. VCU leads the way in Hepatocellular Carcinoma (HCC) data and sample repository collection for HCC in liver transplantation. On 03/28/2006,1R01DK069859-01A1, Genes Related to HCC progression in living donors (LD) and deceased donors (DD) transplant (GR2HCC) was awarded to the VCU liver program director and chairman of the A2ALL HCC subcommittee. The GR2HCC is nested in 6 of the 9 patient enrolling transplant centers of A2ALL utilizing the DCC of A2ALL for data collection and analysis and the Division of Cancer Epidemiology and Genetics of the National Cancer Institutes (NCI) for gene array quality control. Completion of the 3 specific aims in the very productive GR2HCC (more than 10 peer reviewed full length publication and 1/3 to 1/2 study patient enrollment) will be enhanced with the new Transplant Center recruitment. Finally, ancillary studies accompanying the main trial will improve the patient and sample repository for HCC and will increase the quality and quantities of long term living donor outcomes and quality of life study by augmenting donor patient controls with adult living liver donors of VCU liver transplant program pediatric recipients.