This research explores how data from population genome projects in Southeast Asia are mobilized for identity formation beyond the lab. We compare two cases, the Vietnamese Genome Project which is funded by a Vietnamese private conglomerate and the Peranakan Genome Project in Singapore, to elucidate how the results from population genomic projects in Vietnam and Singapore are co-constituted with existing political and cultural narratives, as well as with varying notions of ‘Chinese-ness’. We find that while scientists in Vietnam use genomics to construct the Vietnamese as genetically independent from what is perceived to be an increasingly dominant Chinese geopolitical power, scientists and participants involved in the Peranakan Genome Project emphasize genomic and cultural mixing which happened between Southern Chinese migrants and the indigenous Malay population historically to distinguish from the rest of the ‘Chinese’ population in Singapore. The cases illustrate the different ways in which the actors involved in these two genome projects strategically differentiate and negotiate the ‘bio geo-body’ of the Vietnamese and the Peranakan in relation to the Chinese identity and nationalism, thereby revealing how genomics is intertwined with local and regional histories, culture and politics.