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Approved research

Human Blood Microbiome

Principal Investigator: Professor Ahmed Moustafa
Approved Research ID: 51458
Approval date: January 17th 2020

Lay summary

Human blood was previously thought to be a microbe-free environment, and therefore, a microbial presence in the blood would be interpreted as a pathogenic infection. With the rapid advances in DNA sequencing technologies, it has been recently suggested that blood can normally contain microorganisms even in healthy individuals. The total genetic makeup of microorganisms living in a compartment of a human body, here the blood, is called 'microbiome'. The microbial community can be bacteria, viruses, archaea, or single-cell eukaryotic organisms. Blood microbiome might differ from one person to another due to the health and disease condition. Thus, a disturbance in the composition of the microbial community may lead to an unhealthy microbiome and consequently causing diseases. This project aims to create a catalog of the human blood microbiome and to suggest a common core blood microbiome among individuals. It will also inspect the discrepancies of the blood microbiome in health and different diseases. This may suggest the blood microbiome as a biomarker for early diagnosis of diseases. There have also been contradicting reports on the interaction between human genes and the human microbiome. This interaction between the human genes and the blood microbiome will be addressed. Blood transfusion is a concern because patients, particularly, immunocompromised, may be subjected to further illness if they receive blood contains unexpected (and untested) microbes. Furthermore, the project will establish associations between the blood microbiome composition (presence and load) and the available demographics, lifestyles, and ethnic backgrounds. The project will not only focus on exploring the types of microbes, but it will also determine microbial functional capabilities. This comprehensive characterization will provide insights for potential therapeutic solutions for disease-causing blood microbes.

Current: Blood Microbiome


The construction of the blood microbial catalog in the general population will serve as a reference resource that can be utilized to be compared against to determine whether a sample of interest deviates from the reference, which can potentially be interpreted as a state of a certain disease. We propose analyzing whole-genome DNA samples of peripheral blood to identify and characterize microbiota in the human blood. The project aims at constructing a catalog of the prevalence and abundance of microbial communities in the blood of the general population (without targeting specific infectious diseases).

New: Blood Metabolome


Our blood carries a multitude of metabolites that are highly associated with a range of traits and diseases, including but not limited to diabetes, obesity, heart disease, mental health, and aging. Investigating the association between blood metabolites and health and diseases on the one hand and association with the genetic makeup of the individuals can be a powerful holistic approach to identify novel blood biomarkers for diseases with an enhanced understanding of the genetic and environmental factors. In March 2021, UK Biobank announced the release of the data generated from profiling 249 metabolic measures from 120,000 participants using the Nightingale Health technology. We will employ machine learning approaches (we will test several techniques to determine the optimal performance) to build a predictive model(s) for the relationship between genetic, environmental, blood metabolites, and health and disease conditions.