In contrast, many SHH-1A and SHH-1B cases stained positive for OLIG2 [9/22 (41%) and 8/12 (67%), respectively], whereas positive OLIG2 staining (> 5% of tumor cells) was not encountered in any SHH-2 [0/23 (0%); Chi-Square: 18.849; df: 2; P < 0.001]. This evidence concerns the gene OLIG2 and neoplasm.