“The genetic architecture of adaptations to high altitude in Ethiopia” Gorka Alkorta-Aranburu1, Cynthia M. Beall2*, David B. Witonsky1, Amha Gebremedhin3, Jonathan K. Pritchard1,4, Anna Di Rienzo1* 1 Department of Human Genetics, University of Chicago, Chicago, Illinois, United States of America, 2 Department of Anthropology, Case Western Research University, Cleveland, Ohio, United States of America, 3 Department of Internal Medicine, Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia, 4 Howard Hughes Medical Institute * E-mail:
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[email protected] Corresponding authors: Anna Di Rienzo Department of Human Genetics University of Chicago 920 E. 58th Street Chicago, IL 60637, USA. Cynthia M. Beall Anthropology Department Case Western Reserve University 238 Mather Memorial Building 11220 Bellflower Road Cleveland, OH 44106, USA. 1 ABSTRACT Although hypoxia is a major stress on physiological processes, several human populations have survived for millennia at high altitudes, suggesting that they have adapted to hypoxic conditions. This hypothesis was recently corroborated by studies of Tibetan highlanders, which showed that polymorphisms in candidate genes show signatures of natural selection as well as well-replicated association signals for variation in hemoglobin levels. We extended genomic analysis to two Ethiopian ethnic groups: Amhara and Oromo. For each ethnic group, we sampled low and high altitude residents, thus allowing genetic and phenotypic comparisons across altitudes and across ethnic groups. Genome- wide SNP genotype data were collected in these samples by using Illumina arrays. We find that variants associated with hemoglobin variation among Tibetans or other variants at the same loci do not influence the trait in Ethiopians.