Because the mutation data could be skewed by in vivo selection of specific oncogenic mutations, we examined genes known to be involved in human BCP-ALL (Ptpn11, Bcor, and Trp53) as well as genes that are not known to be involved in BCP-ALL (Cdh23, Pcdha12, and Adgrb3). The gene discussed is PCDHA12; the disease is acute lymphoblastic leukemia.