2025 Theses Doctoral

Latinidad in Precision Medicine: The Boundaries and Extensions of Ethnic Identity in Biomedical Research

Mendoza-Grey, Sonia

Background and research questions.
This dissertation analyzes the social processes and effects of deploying “Latinx” as a crucial population for advancing precision medicine research and practice. Precision medicine is an approach to healthcare that tailors treatment based on genetic understandings of disease and individuals. Sociologists have established that racialized concepts of human, and therefore genomic, differences persist as the operating logic in biomedicine, yet the relevance of race and ethnicity in genomics is contested, and there exists no standard definition of ethnic or racial categories within precision medicine. The questioned relevance of race and ethnicity in genomics is especially salient for the broad ethno-racial social category of Latinx, which straddles racial and ethnic categories.

Thus, focusing on Latinx populations for precision medicine presents a paradox: given that “Latino/a” or “Hispanic” is also institutionalized as the prototypical “ethnic” (read “nonracial”) social category, how can this group function as a meaningful biological, and specifically genetic, category? How might the use of Latinx as a biosocial grouping for the purposes of precision medicine have broader social effects, both on the self-understandings of Latinx people, and on others’ understandings of Latinx as a social and political category? Considering this and the breadth and heterogeneity of the ethno-racial social category of Latinx, this study takes a critical look at how precision medicine investigators conceptualize (and therefore construct) attributes of the Latinx population as “genetically meaningful” through recruitment practices and analyses.

Study methods.
This qualitative study incorporates 34 key informant interviews with precision medicine experts who work with Latinx communities and Latinx data, as well as 40 lay informant interviews with Latinx community members. This work is supplemented by a text analysis of 100 precision medicine publications and ethnographic observations of 23 precision medicine events that aided in crafting the interview guides and understanding the landscape of precision medicine.

Results.
Expert interviews reveal how researchers struggled to categorize the Latinx population through socio-political and biomedical understanding of “Latinx” as a large and ever-changing category, and how these interpretations led experts to adjust and toggle in their methodological or pragmatic research approaches. Expert informants reveal their definitions of “Latinx” through the subdivision of the category into subcomponents they believed carried the essence of Latinidad, which include, but are not limited to, social and cultural factors. Importantly, in characterizing “Latinx genetics,” experts described Latinidad as consisting of continental and racialized “genetic groupings” in the context of “Latinx admixture,” therefore racializing the ethnic Latinx category. Ultimately, researchers shared that their work was motivated by their desire to increase Latinx representation in research. Across precision medicine disciplines, experts also conveyed that socio-structural factors far outweigh genetic impacts on population health, and some researchers were skeptical that precision medicine advances will help Latinx population given the massive disparities in access to state-of-the-art medical technology and care.

Moreover, while sharing their unique composite understanding of what made them Latinx, lay participants described their identity as related to colonial history, and as having complicated associations with colorism. Further, lay informants overwhelmingly endorsed socio-structural determinants of health over genetic understandings of Latinx health. While themes of socio-politics come up as important for experts and lay informants alike, the major point of departure between lay informants and experts is that my lay informants described their genetics as stemming from and revealing their identity’s social histories while never tying genetics to their sense of belonging to the Latinx category.