Most research in cancer microbiomes is carried out in European and North American patients. Patterns in low- and middle-income countries are often assumed based on results from richer countries, despite different diets, living conditions and cancer rates. We previously established an international network of researchers from emerging economies, to train them in methods needed to carry out research on their own populations. This paper is the first of those studies. Researchers in India worked with the team in Leeds to compare the microbiome in stool samples from 46 Indian colorectal cancer patients to 43 volunteers and examined the differences. We found that several of the bacteria which differentiated cancer patient and healthy volunteer were the same as those in other countries, but there were differences, both in some of the bacteria involved, and the overall pattern of changes. Comparing this new data with previous work from multiple countries showed closest similarities with a previous Indian cohort. This emphasizes the point that different countries and regions have different features affecting their cancer risks and development. We can’t continue to assume that we know how cancer develops on one population, based on results from elsewhere. https://genomemedicine.biomedcentral.com/articles/10.1186/s13073-021-00844-8