CREBBP and precursor B-cell acute lymphoblastic leukemia: Deletions and mutations of CREBBP, which encodes the transcriptional coactivators and acetyltransferase CREB binding protein, are found in 18% of relapsed pediatric B-ALL patients, but less than 1% at diagnosis in those who did not relapse [76], suggesting CREBBP gene mutations are associated with relapse of the disease.