Pathology Blood 8ff9497b Chromosome for ABO gene is? A 9q B 10p C 11q D 12p High-Yield Explanation Ans is 'a' i.e. 9q * The ABO gene (Histo-blood group ABO system transferase enzyme) resides on chromosome 9 at the band 9q34.2.Also know* Gene for Rh antigen is located on Chromosome-1