CTLA-4 rs231775 was not associated with risk of osteosarcoma in the main analysis but was significantly associated with osteosarcoma risk in the leave-one-out analysis with a decrease in heterogeneity and significance with the removal of Bilbao-Aldaiturriaga26 In subgroup analysis, the test of subgroup differences was significant indicating that there is a significant effect of race on the pooled OR (Spanish vs. Chinese). This evidence concerns the gene CTLA4 and osteosarcoma.