Hemoglobin calabria leading to undetectable hemoglobin A1C

Abstract

More than 12,000 hemoglobin (Hb) variants have been identified and listed on the HbVar database. Reliable detection of these Hb variants is important for planning hemoglobinopathy screening and genetic counseling. Presumptive diagnosis is usually dependent on dedicated Hb analyzers, e.g. high-performance liquid chromatography (HPLC) or capillary electrophoresis (CE) systems specifically developed for Hb fraction separation and quantification. In most cases, simple Hb variants can be easily identified. Rarely, a novel Hb molecule formed by the assembly of different defective globin chains could complicate clinical and laboratory diagnostics and requires DNA testing