Bisalbuminaemia due to novel mutation at a critical residue involved in recycling; Albumin Lyon (510His → Arg)

The nature and location of the mutation suggest it would have no direct influence on haemostasis through altered warfarin binding or increased fibrinogen attachment and it appears to be incidental to the thrombotic phenotype. However the highly conserved His510 residue is recognised as being of critical importance in albumin recycling through interaction with its savaging neonatal Fc receptor. The normal albumin level of 41.1 g/l and the coequal expression of albumin Lyon demonstrate that the conservative 510His → Arg substitution does not interfere with the pH dependant capture and release of albumin by the receptor.