Using an animal model for the study of murine thymic lymphomas, frequent losses of heterozygosity (LOHs) on six chromosomal regions were reported. To determine the existence of LOH loci in human lymphomas, we screened 43 non-Hodgkin's lymphomas by using polymorphisms mapped in each of the orthologous human region. All LOH regions (1p32-p36, 9p21, 9p22-p23, 9q22-q34 and 10q23-q24) were observed in B-cell lymphomas at different frequencies. In addition, analysis of the tumor suppressor genes, p16(INK4a), p73 and PTEN located in 9p21, 1p36 and 10q23, respectively, revealed the participation of p16(INK4a) and p73 but not of PTEN. Importantly, two subregions of LOH were observed in 9q22-q34, one of them not previously described. Our results support the usefulness of murine models to study human lymphoid neoplasias and reveal novel regions on 9q22-q34 candidate for containing tumor suppressor genes involved in human lymphomas.