HMGN1 and acute lymphoblastic leukemia: Furthermore, 21% (8/38) of pediatric P2RY8::CRLF2 ALL patients harbored +21 (n = 2 + 21c), resulting in a significantly increased HMGN1 expression, and 5% (2/38) harbored iAMP21, also with a significantly higher HMGN1 expression (Figure 1E; p = 0.0075).