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Garcia-Ortiz, H.

Publications and source records attributed to Garcia-Ortiz, H..

3 recordsLinked to original sources

Ancient Mitogenomes from Belize Provide Insights into the Mobility and Migration of Ancient Communities in Mesoamerica and the Caribbean.

Maya peoples have undergone several largescale demographic transformations over the past 3000 years, including the formation and depopulation of large urban centers, climatic events, and multiple colonial regimes. Archaeological and stable isotope evidence from across the Maya lowlands throughout these periods paints a picture of a demographically mobile population with complex and dynamic relationships among some of the largest urban polities in antiquity. The nature of the genomic relationship between ancient Maya urban centers, as well as their relationship with present-day Maya communities, however, remains under-characterized. Here, we present mitogenomic data of 16 ancient Maya Ancestors recovered from interments in the ancient Maya cities of Caracol and Santa Rita Corozal located in Western and Northern Belize. These ancient data were combined with 110 newly collected contemporary individuals from Northern Belize, along with nearly 600 previously published ancient and contemporary comparative mitogenomes recovered from sites spanning Mesoamerica and the Caribbean to reconstruct paleodemographic and mobility patterns of maternal lineages through time. Our results are consistent with broadly interconnected Maya populations that have maintained maternal genetic continuity across much of the Holocene, and which are not structured by linguistic family.

genetics↗

Whole mitogenome analysis highlights demographic history and shared connections among distal Indigenous groups of Mexico Complete mitogenome sequencing from 60 Mexican Native American groups

The study of mitochondrial DNA is a valuable tool to delve into the demographic history of human populations. Particularly in the Americas, five widespread Native American specific mitochondrial lineages have been identified. Here we included the complete mitogenome sequencing of 572 Indigenous individuals belonging to 60 populations spanning the Mexican territory. Our results show a great diversity of matrilineages widespread across the country, revealing shared mtDNA haplogroups in populations from distant regions. We identified all the five main Native American haplogroups clades, including 83 different subhaplogroups, from which nine are novel. The most frequent of the novel haplogroups was A2+64. A phylogenetic inference suggests that A2+64 comes from an ancestral maternal lineage that spread into the Caribbean islands. Additionally, a demographic reconstruction from whole mitogenomes showed an exponential increase in female Ne around 10 Ka ago in all the tested regions. All these findings suggest a genetic persistence through Mexico and possibly the Americas, in agreement with the model of the Mesoamerican-related expansion into the Caribbean and South America.

genetics↗

Genotyping, sequencing and analysis of 140,000 adults from the Mexico City Prospective Study

The Mexico City Prospective Study (MCPS) is a prospective cohort of over 150,000 adults recruited two decades ago from the urban districts of Coyoacan and Iztapalapa in Mexico City. We generated genotype and exome sequencing data for all individuals, and whole genome sequencing for 10,000 selected individuals. We uncovered high levels of relatedness and substantial heterogeneity in ancestry composition across individuals. Most sequenced individuals had admixed Native American, European and African ancestry, with extensive admixture from indigenous groups in Central, Southern and South Eastern Mexico. Native Mexican segments of the genome had lower levels of coding variation, but an excess of homozygous loss of function variants compared with segments of African and European origin. We estimated population specific allele frequencies at 142 million genomic variants, with an effective sample size of 91,856 for Native Mexico at exome variants, all available via a public browser. Using whole genome sequencing, we developed an imputation reference panel which outperforms existing panels at common variants in individuals with high proportions of Central, South and South Eastern Native Mexican ancestry. Our work illustrates the value of genetic studies in populations with diverse ancestry and provides foundational imputation and allele frequency resources for future genetic studies in Mexico and in the United States where the Hispanic/Latino population is predominantly of Mexican descent.

genetics↗