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A letter to the editor is presented in response to the article "The evolutionary adaptation of the C282Y mutation to culture and climate during the European neolithic" by K. Heath and colleagues in a 2016 issue.

The view of scurvy being exclusively a nutritional disorder needs to be updated. Genetic polymorphisms of HFE and haptoglobin (Hp) may explain the geographic variability of mortality caused by the European famine of the mid-19th century. In this period, potatoes had fallen victim to the potato blight and Ireland was more severely hit than continental Europe. Hereditary hemochromatosis is a genetic disorder with mutations in the HFE gene, characterized by iron overload (with a reduced vitamin C stability) and with a predominance of affected men. The Irish have the world's highest frequency of the C282Y mutation and the particular iron metabolism of the Irish helps to understand the size of the catastrophe and the observed overrepresentation of male skeletons showing scurvy. Hp is a plasma α2-glycoprotein characterized by 3 common phenotypes (Hp 1-1, Hp 2-1 and Hp 2-2). When the antioxidant capacity of Hp is insufficient, its role is taken over by hemopexin and vitamin C. The relative number of scurvy victims corresponds with the Hp 2-2 frequency, which is associated with iron conservation and has an impact on vitamin C stability. As iron is more abundant in males, males are overrepresented in the group of skeletons showing scurvy signs.

Background: The European In Vitro Diagnostics (IVD) directive requires traceability to reference methods and materials of analytes. It is a task of the profession to verify the trueness of results and IVD compatibility., Methods: The results of a trueness verification study by the European Communities Confederation of Clinical Chemistry (EC4) working group on creatinine standardization are described, in which 189 European laboratories analyzed serum creatinine in a commutable serum-based material, using analytical systems from seven companies. Values were targeted using isotope dilution gas chromatography/mass spectrometry. Results were tested on their compliance to a set of three criteria: trueness, i.e., no significant bias relative to the target value, between-laboratory variation and within-laboratory variation relative to the maximum allowable error., Results: For the lower and intermediate level, values differed significantly from the target value in the Jaffe and the dry chemistry methods. At the high level, dry chemistry yielded higher results. Between-laboratory coefficients of variation ranged from 4.37% to 8.74%. Total error budget was mainly consumed by the bias. Non-compensated Jaffe methods largely exceeded the total error budget. Best results were obtained for the enzymatic method. The dry chemistry method consumed a large part of its error budget due to calibration bias., Conclusions: Despite the European IVD directive and the growing needs for creatinine standardization, an unacceptable inter-laboratory variation was observed, which was mainly due to calibration differences. The calibration variation has major clinical consequences, in particular in pediatrics, where reference ranges for serum and plasma creatinine are low, and in the estimation of glomerular filtration rate.