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Indigenous people from the American continent, or Native Americans, are underrepresented in the collective genomic knowledge. A minimal percentage of individuals in international databases belong to these important minority groups. Yet, the study of native American genomics is a growing field. In this work, we reviewed 56 scientific publications where ancient or contemporary DNA of Native Americans across the continent was studied by array, whole-exome, or whole-genome technologies. In total, 13,706 native Americans have been studied with genomic technologies, of which 1292 provided whole genome samples. Data availability is lacking, with barely 3.6% of the contemporary samples clearly accessible for further studies; in striking contrast, 96.3% of the ancient samples are publicly available. We compiled census data on the home countries and found that 607 indigenous groups are still missing representation in genomic datasets. By analyzing authorship of the published works, we found that there is a need for more involvement of the home countries as leads in indigenous genomic studies. We provide this review to aid in the design of future studies that aim to reduce the missing diversity of indigenous Americans.

There has been limited study of Native American whole genome diversity to date, which impairs effective implementation of personalized medicine and a detailed description of its demographic history. Here we report high coverage whole genome sequencing of 76 unrelated individuals, from 27 indigenous groups across Mexico, with more than 97% average Native American ancestry. On average, each individual has 3.26 million Single Nucleotide Variants and short indels, that together comprise a catalog of 9,737,152 variants, 44,118 of which are novel. We report 497 common Single Nucleotide Variants (with allele frequency > 5%) mapped to drug responses and 316,577 in enhancer or promoter elements; interestingly we found some of these enhancer variants in PPARG, a nuclear receptor involved in highly prevalent health problems in Mexican population, such as obesity, diabetes, and insulin resistance. By detecting signals of positive selection we report 24 enriched key pathways under selection, most of them related to immune mechanisms. No missense variants in ACE2, the receptor responsible for the entry of the SARS CoV-2 virus, were found in any individual. Population genomics and phylogenetic analyses demonstrated stratification in a Northern-Central-Southern axis, with major substructure in the Central region. The Seri, a northern group with the most genetic divergence in our study, showed a distinctive genomic context with the most novel variants, and the most population specific genotypes. Genome-wide analysis showed that the average haplotype blocks are longer in Native Mexicans than in other world populations. With this dataset we describe previously undetected population level variation in Native Mexicans, helping to reduce the gap in genomic data representation of such groups.