Fungi have been observed to exhibit resistance to high levels of ionizing radiation despite sharing most DNA repair mechanisms with other eukaryotes. Radioresistance, in fact, is such a common feature in fungi that it is difficult to identify species that exhibit widely different radiosensitivities, which in turn has hampered the identification of genetic elements responsible for this resistance phenotype. Due to the inherent mutagenic properties of radiation exposure, however, this can be addressed through adaptive laboratory evolution for increased ionizing radiation resistance. Here, using the black yeast Exophiala dermatitidis, we demonstrate that resistance to γ-radiation can be greatly increased through repeated rounds of irradiation and outgrowth. Moreover, we find that the small genome size of fungi situates them as a relatively simple functional genomics platform for identification of mutations associated with ionizing radiation resistance. This enabled the identification of genetic mutations in genes encoding proteins with a broad range of functions from 10 evolved strains. Specifically, we find that greatly increased resistance to γ-radiation is achieved in E. dermatitidis through disruption of the non-homologous end-joining pathway, with three individual evolutionary paths converging to abolish this DNA repair process. This result suggests that non-homologous end-joining, even in haploid cells where homologous chromosomes are not present during much of the cell cycle, is an impediment to repair of radiation-induced lesions in this organism, and that the relative levels of homologous and nonhomologous repair in a given fungal species may play a major role in its radiation resistance.

There has been a marked change in recent years in the climate of ideas about industrialisation in developing economies and it is fortunately no longer necessary to argue in favour of industrialisation in opposition to another approach to economic development. Yet it is still necessary to continue to state the basic case, particularly since Africa is industrially the least developed of all the continents. The doctrine that industry is the key to economic development is of comparatively recent origin. Its antecedents are the writings of Professor G. Myrdal and Dr R. Prebisch and the practical achievements of the U.S.S.R. and Japan.

The present book, which has been prepared under the auspices of the Committee on International Organisations of the U.S. Social Science Research Council, is essentially a collective effort by a group of American and British scholars. There are two methodological chapters which govern the systematic and common approach to how decisions are made in eight organisations, and a concluding synthesis. The organisations covered are the International Telecommunications Union (I.

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Economic integration has been in the forefront of discussion in Africa since the massive movement towards independence in the late 1950's and early 60's. There was immediate recognition that, while independence had been the primary goal, African frontiers were largely an artificial by-product of the colonial scramble 60 to 70 years ago, that many African countries were too small to be economically viable, and that to transform political into economic independence necessarily required concerted action. Further impetus was given to thinking and discussion by the setting up of the Economic Commission for Africa in 1958 and of the Organisation of African Unity in 1963. Concepts, of course, varied, as the pre-history of the O.A.U. shows clearly. The radical Casablanca group stood for an all-African common market, to lead rapidly to an all-African government. The member states of the Union africaine et malgache had much more limited but also more precise objectives: especially continued close co-operation among the francophone countries, and association with the European Common Market, particularly France. There were other ideas and associations, often cutting across these two main groupings. Yet it is perhaps only recently that views are beginning to clarify and that the real difficulties involved are being realised, a condition precedent for progress in practice. Economic integration has to be seen as an ultimate goal, with a number of concrete intermediate steps involving ever-increasing economic cooperation among groups of countries.