Abstract
Various relics ascribed to have been in physical contact with the historical Jesus of Nazareth have been evaluated for the presence of blood, including the Tunic of Argenteuil, the Sudarium of Oviedo, and most famously, the Shroud of Turin. Interestingly, the blood type on all three textiles was found to be AB by serological testing; a similar result was observed for various modern Eucharistic miracles, in which consecrated hosts are reported to change into human cardiac tissue and blood. As AB is a relatively rare blood type, these collective observations have been used in numerous contemporary media outlets to support the idea that all such objects share a common origin. Here, the scientific validity of mutual blood type expression is evaluated. As discussed, AB antigens are not unique to human red blood cells but are also expressed in bacteria, providing a practical connection between such varied objects. Moreover, this article clarifies that the communal presence of specific and unique polymorphic markers would be required to validate that bloodstains associated with such items truly originate from a single source.