Аннотация:SUMMARY DNAs from human malignant melanoma cells and autologous peripheral blood lymphocytes were evaluated by Southern blot analysis with probes for class I and II HLA genes. DNA of melanoma cells digested with PvuII, EcoRI and BglI and hybridized with a DRB probe showed a loss of several fragments when compared with DNA from lymphocytes. The same DNAs were not distinguishable when hybridized with a DQB probe. Analysis of melanoma and autologous lymphocyte DNAs from the same patient with a class I cDNA, after digestion with several endonucleases, revealed a further loss of fragments in melanoma cells. Comparison of restriction fragment patterns of melanoma and lymphocytes with those of homozygous, serologically‐typed cell lines indicated that melanoma cells have lost fragments diagnostic of DR2 and A1 antigens. A densitometric analysis of signals of several oncogenes in comparison with that of DR indicated that a duplication of the remaining DR allele had occurred in melanoma cells.
