The finding of this study is in agreement with a recent study reported from Korean population with 65 RCC patients who received sunitinib therapy, which also reported a significant association of ABCG2 421C>A with grade 3 and grade 4 thrombocytopenia (P-value = 0.04, OR = 9.90).[22]. This evidence concerns the gene ABCG2 and Thrombocytopenia.