||This contribution draws on ethnographic research conducted in Oman on inherited blood disorders (IBD). By interpreting results from population genomics studies that trace mutation processes over centuries of human activities, lay-representations of IBD often consider them historical evidence. The perceived spread of IBD in Oman may thus provide unusual historical depth in a country where past conflicts have been erased from historiography and representations of time are politically prescribed. Through the notions of crisis and diversification, this contribution shows how IBD's chronicity challenges the healthcare system and became a national issue, politically labelled as urgent. The paper casts light on several aspects of contemporary Omani society: it first addresses the dynamics of disease taxonomies – although biomedically described in the early twentieth century, IBD were not individualized within local nosologies until the 1970s. Secondly, it shows how biomedical knowledge about IBD led to diversification within the healthcare system, through the introduction of clinical genetics, genomics, and community genetics. Thirdly, it attempts to broach modalities of the biopower exerted by the Omani regime over its citizens: IBD are targeted by various public health measures that jeopardize patients’ autonomy by aiming to control their bodies through their matrimonial behaviour. In addition, two aspects of the intersections between Omani social hierarchy and IBD are noteworthy: the creation of a patients’ association that constitutes a potential disturbance of the social order; and the way IBD mutations traced by genomics are considered direct historical documents that challenge representations of the recently crafted ‘Omanity’ in a context of regional concern regarding national identities’ durability.