Calculation of the ratio between NOTCH2 and N2N PCR products levels in DNA from tumor and lymphocytes derived from the same patient, evaluates the gene copy status at NOTCH2 relative to N2N. In 100% (21/21) of OG displaying 1p loss (haplotype H10), this test showed imbalance between the duplicated regions: exons 1 and 4 of NOTCH2 harbored half copy number relative to N2N, indicating loss of one NOTCH2 copy compared to N2N (OD 087, Figure 3B). This evidence concerns the gene NOTCH2 and neoplasm.