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A/P Tan Boon Huat, T. B. T.

Publications and source records attributed to A/P Tan Boon Huat, T. B. T..

3 recordsLinked to original sources

Early and current environments exert distinct effects on immune function in the Orang Asli

Humans evolved in environments characterized by subsistence foraging and hunting, high levels of physical activity, and regular and diverse pathogen exposure. Industrialization has rapidly altered these environments, leading to increased metabolic and inflammatory disease risk. These observations have motivated studies of how industrialization shapes immune function, but whether industrialization alters immune biology through developmental embedding of early-life environments or ongoing plastic responses to current conditions remains poorly understood. To address this gap, we worked with the Orang Asli--the Indigenous peoples of Peninsular Malaysia--who currently span a gradient from subsistence horticulture, foraging, and hunting to industrialized, urban environments with substantial inter-individual variation in life course experiences. Leveraging continuous measures of both early-life and current lifestyle, we found that current lifestyle exerts stronger effects on adult immune gene expression than early-life conditions, impacting 1,428 as compared to 223 genes, respectively. Early-life associated genes were enriched for pathways regulating adaptive immunity, particularly T cell development and differentiation, consistent with higher predicted T cell abundance and circulating IL-8 in urban-born individuals. In contrast, current exposure to urban, industrialized conditions was linked to innate immune and inflammatory activation, including dendritic cell abundance, metabolic pathway upregulation, and elevated CRP. Finally, consistent with lower rates of immune disorders in non-industrial settings, current exposure to this lifestyle was associated with up-regulation of genes involved in Th1/Th2 differentiation. Together, these results emphasize that industrialized immune profiles reflect both early-life developmental embedding and ongoing environmental responses, highlighting the importance of considering exposures across the life course. Significance statementHumans evolved in environments with high levels of physical activity, subsistence-based diets, and constant pathogen exposure. Rapid industrialization has dramatically changed these conditions, coinciding with rising rates of non-communicable diseases with inflammatory underpinnings. Our study with the Orang Asli, the Indigenous peoples of Peninsular Malaysia, tests how exposure to industrialization across the life course shapes immune variation. We find that early-life environments leave lasting marks on adaptive immune function particularly T cells, while industrialized adult lifestyle influences innate immune activity and inflammation. These results clarify how different stages of life contribute to immune remodeling and point to a mechanistic link between industrialization and disease risk, highlighting the importance of both early-life and current environments in shaping later life health.

genetics↗

Development and assessment of tailored illustrations to enhance community understandings of genetics topics

ObjectivesEffective communication about genetics concepts is essential for collaborative anthropological genetics research. However, communication can be challenging because many ideas are abstract and may be especially unfamiliar to communities with limited access to formal education. Indeed, there are no widely adopted models for communicating such information, nor a clear understanding of the social factors that may shape participant engagement. Here, we conducted a qualitative and quantitative, community-driven study to understand how illustrations can be useful to support concept sharing with two Indigenous groups--the Orang Asli of Peninsular Malaysia and the Turkana of Kenya. MethodsWe used a two phase approach to create and evaluate how illustrations can bolster communication about genetics concepts. First, we created images illustrating answers to frequently asked questions about genetics, iteratively updating the illustrations based on participant feedback. Second, we conducted 92 interviews to evaluate the finalized illustrations effectiveness. Finally, we analyzed the interview data using thematic analyses, multivariable modeling, and multiple correspondence analyses to identify patterns in participant understanding and feedback, including age, sex, market integration, and schooling. ResultsParticipants reported high interest in genetics research (92%) and broadly positive perceptions of the illustrations. Familiar, locally-grounded imagery was preferred and associated with greater perceived clarity, while more technical illustrations were more frequently reported as confusing. Quantitative analyses showed strong internal consistency across measures of engagement and understanding, with modest variation by degree of market-integration, schooling, and sex. DiscussionOur findings demonstrate that community-specific visualizations, co-developed through iterative feedback, can effectively support engagement with genetics research in participant communities.

scientific communication and education↗

Early life environments shape adult cardiometabolic health during rapid lifestyle change

Early life environments can have long-lasting impacts on health and fitness, but the evolutionary significance of these effects remains debated. Two major classes of explanations have been proposed: developmental constraints (DC) explanations posit that early life adversity limits optimal development, leading to long-term costs, while predictive adaptive response (PAR) explanations posit that organisms use early life cues to predict adult conditions, resulting in detriments when adult environments do not match expectations. We tested these hypotheses using anthropological and biomedical data for the Orang Asli--the Indigenous peoples of Peninsular Malaysia--who are undergoing a rapid but heterogenous transition from non-industrial, subsistence-based livelihoods to more industrialized, market-integrated conditions. Using questionnaire data, we show that this shift creates natural variation in the degree of similarity between early life and adult environments. Using anthropometric and health data, we find that, more rural, subsistence-based early life environments are associated with shorter stature but better adult cardiometabolic health. Applying a quadratic regression framework, we find support for DC but not PAR in explaining adult cardiometabolic health, echoing findings and conclusions from other long-lived species. Overall, our results suggest that early life conditions can provide additive protection against common health issues associated with urban, industrialized lifestyle exposure.

evolutionary biology↗