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Biomedical subjects

J Ruffié

Publications and source records attributed to J Ruffié.

9 recordsLinked to original sources

[Study of equivalents of rhesus antigens in non-human primates].

Human alloantibodies specific of some Rh antigens cross-react with non human primates red blood cells. These crossreactions demonstrated that only African apes express equivalents of Rho (D) and hr' (c). The antigenic resemblance between these two human antigens and their primate homologues is confirmed by the reactivities of human anti-D and anti-c monoclonal antibodies. The use of a human Rh cDNA probe allowed to confirm by Southern blot hybridization that nonhuman primates possess Rh-like genes. The number of Rh-like genes per haploid genome was deduced from the results obtained with exon-specific probes.

Animals

[Geographical hematology and population dynamics].

Hemotypology, which is based on the study of a large number of immunological and enzyme systems in the blood, has shown the extraordinary polymorphism of the human species and the lack of a genetic barrier between groups once considered as separate races. The typological mode of thought predominated in anthropology until the middle of this century. Mankind was divided into races according to a theoretical profile characteristic of each one, the holotype, which all the members of the same race were thought to resemble. Today we tend toward the substitution of population thinking: the human species, like all the other animal or plant species, is made up of populations, reproductive units whose members are more likely to mate within the group than outside it. A population is never totally closed and it is the interpopulational genetic flux which assures the homogeneity of the species. Three factors play a fundamental role in the genetic structure of human populations: 1. An ancestral genetic heritage from the distant past is modified by external contribution such as genetic flux and hybridization; 2. Chance is an especially important factor in very isolated small groups; 3. Natural selection: the majority of all genetic factors are not neutral, as we used to think, but possess a certain selective value. This nonneutrality doubtless explains the maintenance of the hemotypological polymorphism in man, as in the model proposed by A.E. Mourant and J. Ruffié. Following these ideas, sometimes it is possible to find the hemotypological traces of important events, especially of the great migrations of the beginning of the neolithic or the beginning of the historic period. Examples are cited which concern the peopling of sub-Saharan Africa, the western Mediterranean and western Europe, and of the continental Far East and Japan. This conceptual revolution, based on the dynamic idea of populations and not on that of the typological conception of race, has shed new light on the science of anthropology and has bridged the gap between hematology and history.

Africa, Northern

[Study of the Gc protein in several French population samples : genetic polymorphism by isoelectrofocusing and quantitative results].

The authors describe the results obtained in an examination by isoelectrofocusing of more than 1,000 serum samples from various regions in France. The autochthonous populations of the north side of the Pyrénées are characterized by a high frequency of the gene Gc2 and a very low frequency of the Gc1F gene. This distinguishes them from the other groups studied (southwestern, northwestern and eastern France). The quantitative analysis of the data emphasizes the difference. These results can only be explained by the interdependance of the genetic and metabolic factors.

Adult

[Hematology, genetics and ethnology (author's transl)].

The concept of geographical haematology described by Jean Bernard in 1965-1966, found a remarkable application field in Anthropology. The human ecology which allows to measure the influence of environmental factors in man through some haematological variations, has been added to the genetics of human populations, revealed by the blood groups discovery. It has been now demonstrated that, in man, cultural or sociological features can act a genetical isolation more effective that natural boundaries. So, an ethnological haematology is superimposed on the geographical haematology of which it can modify outlines.

ABO Blood-Group System

[Conversion of chimpanzee O-erythrocytes into B-erythrocytes by human alpha galactosyltransferase].

The red blood cell antigens of the ABO system are not present in all the anthropïd Primates. The Chimpanzee, particularly, shows only the two genes A and O. The alpha-galactosyl transferase, present in the human sera of group B, has been used to fix a molecule of galactose on O red cells of Chimpanzee giving them a B specificity. If the B gene was present in the Chimpanzee it could consequently be expressed on the erythrocytes. This gene, probably present in an ancestor common to the anthropoïd apes and to Man disappeared in the Chimpanzee, perhaps at the origin of species.

ABO Blood-Group System

[Certain human anti-Gm antisera have an antiglobulin reacting specifically with IgG of baboons].

An antiglobulin anti-Baboon IgG exists in human sera [with or without an anti-Gm (1)]. There is no correlation between this antiglobulin and another one of the Milgröm type. Its occurrence is not characteristic of the anti-Gm sera. Therefore, it cannot explain the different specificities between the two types of anti-Gm (1) discordant at the level of non-human Primate immunoglobulins.

Animals

[Populational speciation or chromosomal speciation? About the book of Jean de Grouchy "From the birth of species to the aberrations of life" (author's transl)].

According to Jean de Grouchy, the emergence of a new species is dependent on an "acceptable" chromosomic rearrangement, which passing from the heterozygous state (in the original bearer) to the homozygous state (in some of his enbred offspring) becomes definitively established and creates a population sexually isolated from its acestors. He is thus using the idea of karyotype to develop the typological theory put forward at the beginning of the century which postulates that a single mutant is at the origin of a new species. Although he gives an important place to chromosomic rearrangements in the sexual isolation of a new species, J. Ruffié demonstrates by arguments taken from population genetics and from the immunological polymorphism of wild populations that speciation is almost always the result of the evolution of an entire group, which, because of geographic isolation, drift, and differential selection, diverges from the ancestral branch and finally becomes totally incapable of breeding with it. He proposes a model of speciation which includes the two processes population and cytologic. At a first step, the group is isolated geographically and continues its independent evolution; the second step consists of chromosomic recombinations which render the sexual isolation complete. The modifications of the karyotype make the process of speciation irreversible.

Adaptation, Physiological