How does DNA reshape our understanding of ancestry, colonial society, and identity in the Americas? In this course, we will explore the science and methodology of genetic genealogy through the lens of first contact between European and Indigenous peoples. Using the New Mexico DNA Project as a central case study, we will examine how Y-DNA and mitochondrial DNA can confirm, complicate, and challenge traditional research. Topics include Y-DNA Adam, Indigenous maternal haplogroups, the Spanish castas system, and colonial identity. We will consider the ethical and political implications of DNA testing and the limits of what genetic evidence can, and cannot, reveal about race and belonging.