Medical Genetics and the First Studies of the Genetics of Populations in Mexico.

Following World War II (WWII), there was a new emphasis within genetics on studying the genetic composition of populations. This probably had a dual source in the growing strength of evolutionary biology and the new international interest in understanding the effects of radiation on human populations, following the atomic bombings in Japan. These global concerns were shared by Mexican physicians. Indeed, Mexico was one of the leading centers of this trend in human genetics. Three leading players in this story were Mario Salazar Mallén, Adolfo Karl, and Rubén Lisker. Their trajectories and the international networks in human genetics that were established after WWII, paved the way for the establishment of medical and population genetics in Mexico. Salazar Mallén's studies on the distribution and characterization of ABO blood groups in indigenous populations were the starting point while Karl's studies on the distribution of abnormal hemoglobin in Mexican indigenous populations showed the relationships observed in other laboratories at the time. It was Lisker's studies, however, that were instrumental in the development of population genetics in the context of national public policies for extending health care services to the Mexican population. In particular, he conducted studies on Mexican indigenous groups contributing to the knowledge of the biological diversity of human populations according to international trends that focused on the variability of human populations in terms of genetic frequencies. From the start, however, Lisker was as committed to the reconstruction of shared languages and practices as he was to building networks of collaboration in order to guarantee the necessary groundwork for establishing the study of the genetics of human populations in Mexico. This study also allows us to place Mexican science within a global context in which connected narratives describe the interplay between global trends and national contexts.