Tcf1−/− samples without a tumor were distinguished by low expression of the following factors: Emp1, Krt8, Runx2, CD44, Fn1, Jag1, Id2, and Cdh1. Several of these genes are known to be Wnt target genes (Runx2, Id2, CD44, and Fn1). The gene discussed is ID2; the disease is neoplasm.