Démographie historique et génétique des populations : la concentration géographique d'une maladie héréditaire rare

Historical and genetic demography the geographical concentration of Alain BIDEAU Henri PLAUCHU rare hereditary disease Albert JACQUARD The Rendu-Osler disease is caused by mutation gene transmitted by autosomic domination The vitality of the carrier-families ensures the perennial continuity of this slightly disadvantageous gene with low mutation rate Although there may be considerable variation in the forms manifested by this gene its degree of penetration is close to 100 this means that for any person affected by the disease it will always be found that one of the parents has been similarly affected and that the transmission of the gene can be traced back genealogically If cases can be found in two families of two persons afflicted with this disease and if be tracing back their genealogies for several centuries common ancestor can be established it may be reasonably concluded that the disease was transferred from the infected ancestor through succeeding generations to each of the present sufferers The inital purpose of our study was therefore to find as many as possible of the families afflicted by the Rendu-Osler disease in one of the villages Chezery where it had most frequently occurred Subsequently through retrospective and comparative analysis we endeavoured to determine which person or persons had served as original transferents of the disease Following the compilation of this data we were able to proceed with the historical and genetic demography Owing to the presence of dominant genetic mutation which over centuries of transference had become biological and historical pointer it was possible to draw distinction between populations afflicted and unafflicted by the disease Differential analysis of the demographic and social behaviour of these two sub- populations is subject of further interest The demographic and genetic details available for each family enable one to retrace their history and hence to gain insight into the biological sociological geographical and genetic factors that have contributed towards shaping the present epidemological profile of the Rendu-Osler disease thus enabling us to learn about the epidemiology hereditary disease and to study its causalityBideau Alain, Plauchu Henri, Jacquard Albert. Démographie historique et génétique des populations : la concentration géographique d'une maladie héréditaire rare. In: Annales. Économies, Sociétés, Civilisations. 34ᵉ année, N. 1, 1979. pp. 85-105