We report the initial characterization of the gastrointestinal tract (gut) and oral microbiota (bacteria) in 32 urban Pakistani adults. Study participants were between ages 18 and 40, had body mass index between 18 and 25 Kg/m 2 , and were students or early-career professionals. These individuals donated a total of 61 samples (32 gut and 29 oral) that were subjected to 16S ribosomal RNA (rRNA) gene sequencing. Microbiome composition of Pakistani individuals was compared against the uBiome database of selected individuals who self-reported to be in excellent health. We observed strong gender-based differences in the gut microbiome of Pakistani individuals, a skewness toward Firmicutes, and unusually high levels of Proteobacteria in the Pakistani men. These observations may indicate microbiota dysbiosis, though 16S data alone can neither establish cause nor effect to human health. Albeit conducted on a smaller scale, our report provides a first snapshot about the composition and diversity of gut and oral microbiota communities in Pakistani individuals.

We describe the characterization of the gastrointestinal tract (gut) and oral microbiota (bacteria) in 32 urban Pakistani adults representing seven major geographies and six ethnicities in the country. Study participants were between ages 18 and 40, had body mass index between 18 and 25 Kg/m 2 , and were early-career students or professionals belonging to 25 major cities of the country. These individuals donated a total of 61 samples (32 gut and 29 oral) that were subjected to 16S ribosomal RNA (rRNA) gene sequencing. Microbiome composition of Pakistani individuals was compared against the uBiome database of selected individuals who self-reported to be in excellent health. Using the crude measure of percentage overlap or similarity between the gut microbiota profile of Pakistani and uBiome dataset as proxy for health, our sequencing indicated that the Pakistani gut microbiota was moderately healthy relative to the uBiome dataset and Pakistani women appeared healthier relative to men. The Pakistani gut microbiome seemed susceptible to obesity and weight gain, levels of probiotics was very high likely due to the popularity of milk-based and fermented foods in the Pakistani diet, and bacteria that metabolize starch and carbohydrates (typically seen in the gut microbiota of honey bee) were abnormally enriched in the gut of Pakistani men. Our investigations reveal serious issues with the dietary habits and lifestyle of Pakistani individuals of consuming food enriched in high carbohydrates and fats, overcooked in oil and spices, following a sedentary lifestyle, little or no daily intake of fresh fruits, over-consumption of antibiotics from a very early age, and health and hygiene standards that do not meet international standards. Our sequencing is the first step towards generating a countrywide understanding of the impact of the local diet and lifestyle on Pakistani gut microbiota and can help understand its overall association with health and wellness.