Scientect

Yahaya Sumara Sulley^1,3*, Ramadan Zakaria Danaa^2,3, Aisha Abdulai^2,3, Abdul Razak Inusah^2,3, Isaac Oboakoh^1,3, Lydia Quansah^1,2,3
1 Department of Forensic Sciences, Faculty of Biosciences, University for Development Studies, Ghana
2 Department of Biotechnology, Faculty of Biosciences, University for Development Studies, Ghana
3 Dr Quansah Lab, (QLab) University for Development Studies, Ghana

Date: 17 August 2024

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Background

The human microbiome, a complex community of microorganisms residing on and within our bodies, plays a pivotal role in health and disease. Its composition is not uniform across individuals; instead, it varies significantly across geographic locations, influenced by environmental factors, lifestyle choices, and genetic background (1).

Understanding these variations is crucial, particularly in fields such as forensic science, where microbiome analysis is emerging as a potential tool. The study of the microbiome has evolved rapidly over the past few decades, with early research focused on identifying microbial species and understanding their roles in health. Today, advanced techniques enable us to explore the complex interactions between microbes and their human hosts, revealing how our geolocation, environment and lifestyle shape these microbial communities.

People’s geolocational disposition which may include environmental factors such as temperature, humidity, and exposure to pollutants are key determinants of their microbial diversity. Urban populations, for instance, tend to exhibit varied microbial diversity compared to rural populations, a difference attributed to factors like diet and lifestyle (2). These variations show the complex relationship between our environment and the microbial communities that inhabit our bodies.

Ethnicity and lifestyle are significant contributors to microbiome composition. For example, studies have shown that African populations typically possess higher microbial diversity and unique microbial profiles compared to Western populations, influenced by factors such as skin pigmentation and climate (3). These differences can have profound implications, particularly in forensic microbiome analysis, where understanding the link between ethnicity and microbiome composition is crucial.

Beyond forensic science, these insights into microbiome diversity can also inform public health strategies. For instance, understanding the unique microbial profiles of different ethnic groups could lead to more personalized approaches to healthcare, improving outcomes in disease prevention and treatment.

Case Box

For example, in a study comparing children in Finland, Russia, and Estonia, countries with differing rates of early-onset autoimmune diseases, researchers found notable differences in gut microbiomes. Finnish and Estonian children, who had lower rates of these diseases, had higher levels of Bacteroides species in their gut microbiomes. In contrast, Russian children had higher levels of E. coli. Further tests showed that LPS (lipopolysaccharide) from E. coli could protect mice from developing diabetes symptoms, suggesting that early-life microbiomes might influence the risk of autoimmune diseases in humans (4).

Forensic Applications of Microbiome

Forensic microbiome analysis, though still in its nascent stages, holds significant promise as a complementary tool to traditional forensic methods. However, challenges such as the time-wise stability of microbiome samples ex-vivo and intra- and inter-individual variation need to be addressed to realize its full potential.

Compared to traditional DNA analysis, microbiome analysis offers the advantage of providing additional context about an individual’s environment and lifestyle. However, it also raises ethical and privacy concerns, particularly regarding the use of personal microbiome data in legal contexts. Addressing these issues will be crucial as microbiome analysis becomes more integrated into forensic investigations.

Metabolomics, the study of small molecules within cells or bodily fluids, provides a snapshot of metabolic processes at a specific point in time (5). This approach has significant potential in various fields, including precision nutrition and personalized medicine. Metabolomics can offer insights into an individual’s lifestyle and environmental exposures, further enhancing the utility of microbiome analysis.

Future research in this area should focus on refining multi-omics approaches to capture the full complexity of the human microbiome. By integrating metabolomics with other techniques, we can gain a more comprehensive understanding of how microbiome variations impact health, disease, and forensic outcomes.

Conclusion

Understanding the human microbiome’s diversity across different populations and environments is essential for advancing its applications in health, hygiene, and forensic science. While challenges remain, particularly in the forensic field, the potential benefits of microbiome analysis, supported by multi-omics approaches, cannot be overstated.

Continued research in this area will be crucial in unlocking new possibilities for personalized medicine and forensic investigations. Key areas for future exploration include improving the stability of microbiome samples, addressing ethical considerations, and developing more robust techniques for analyzing the complex interactions within microbial communities.

Acknowledgements

We would like to extend our sincere gratitude to the Quansah Lab members especially Ayisha Issah and Habib Mutalib for their invaluable support throughout this project.

Authors’ Contributions

Yahaya Sumara Sulley led the writing. Ramadan Zakaria Danaa contributed significantly to the drafting and revision stages of the manuscript. Aisha Abdulai and Abdul Razak Inusah, worked on multiple drafts and provided valuable input for the final version. Lydia Quansah and Isaac Oboakoh, supervised the entire manuscript preparation, ensuring adherence to academic standards and guiding the publication process.

REFERENCES

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2.        Warinner C, Speller C, Collins MJ, Lewis CM. Ancient human microbiomes. J Hum Evol. 2015 Feb 1;79:125–36.

3.        Brim H, Yooseph S, Zoetendal EG, Lee E, Torralbo M, Laiyemo AO, et al. Microbiome analysis of stool samples from African Americans with colon polyps. PLoS One. 2013 Dec 20;8(12):e81352.

4.        Vatanen T, Kostic AD, D’Hennezel E, Siljander H, Franzosa EA, Yassour M, et al. Variation in microbiome LPS immunogenicity contributes to autoimmunity in humans. Cell. 2016 May 5;165(4):842–53.

5.        Locci E, Bazzano G, Chighine A, Locco F, Ferraro E, Demontis R, et al. Forensic NMR metabolomics: one more arrow in the quiver. Metabolomics. 2020 Nov 1;16(11).