[José Martins da Cruz Jobim: his priority in the detection of an hereditary hematologic disorder in African Negro slaves (author's transl)].

A brazilian physician, José Martins da Cruz Jobim, may be considered the author of one of the earliest medical reports with a story of the prevalence of the sikle cell trait among african negroes who came to Brazil as slaves, by observing their rather remarkable resistance against malarial infections than other sets of our population. Naturally, his report, published in 1835, must be considered by the actual scientific concepts.