How Genes Have Illuminated the History of Early Americans and Latino Americans

Abstract

The American continent currently accounts for 15% of the world population. Although first settled thousands of years ago and fitting its label as "the New World," the European colonial expansion initiated in the late 15th century resulted in people from virtually every corner of the globe subsequently settling in the Americas. The arrival of large numbers of immigrants led to a dramatic decline of the Native American population and extensive population mixing. A salient feature of the current human population of the Americas is, thus, its great diversity. The genetic variation of the Native peoples that recent immigrants encountered had been shaped by demographic events acting since the initial peopling of the continent. Similarly, but on a compressed timescale, the colonial history of the Americas has had a major impact on the genetic makeup of the current population of the continent. A range of genetic analyses has been used to study both the ancient settlement of the continent and more recent history of population mixing. Here, I show how these two strands of research overlap and make use of results from other scientific disciplines to produce a fuller picture of the settlement of the continent at different time periods. The biological diversity of the Americas also provides prominent examples of the complex interaction between biological and social factors in constructing human identities and of the difficulties in defining human populations.

Polymorphisms of ADME-related genes and their implications for drug safety and efficacy in Amazonian Amerindians

“…Most pharmacogenetic studies focus on Caucasian populations, which cannot necessarily be extrapolated reliably to the application of PGx in other ethnic groups, such as Amerindian, which may have a unique genetic profile resulting from prolonged geographic isolation and inbreeding 24,25 . There have been relatively few studies of molecular biomarkers in Amerindian populations, highlighted by the fact that they are absent from the 1000 Genomes database, the largest available collection of data on human genetic variability.…”

The Genetic Diversity of the Americas

“…The most prominent of these are Native American populations, which have been the focus of genetics research for many decades. The study of these populations has provided a range of novel insights into the evolutionary history of America, including uncovering complex and prolonged migratory patterns from East Asia during the pre-Columbian settlement of the continent (81,90). These findings underline the heterogeneous Old World ancestry of Native Americans.…”

“…A range of studies date the initial settlement of the American continent towards the end of the last glaciation, some 15,000 years ago, by people who migrated from northeast Asia across Beringia (the land bridge that connected Asia and North America at the time) into Alaska (29,81,90). From the northwest tip of North America, humans dispersed southward, reaching Tierra del Fuego at the southern tip of South America in perhaps as little as 1,000 years.…”

Uniparental ancestry markers in Chilean populations

“…This pattern of a significantly larger contribution of Native American ancestry from the matrilineage than from the patrilineage is consistent with that reported in previous studies from South America (Martinez-Marignac et al , 2004; Bonilla et al , 2005; Vieira-Machado CD, 2011, Dissertation, Universidade Federal do Rio de Janeiro). This phenomenon is attributed to marriages that took place between European men and Native American women during the colonization of the American continent (Ruiz-Linares, 2014). …”