Characterization of G6PD deficiency in southern Croatia: description of a new variant, G6PD Split.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency protects from severe forms of malaria. It is interesting therefore to analyze the molecular basis underlying G6PD deficiency in regions such as the Mediterranean basin where malaria was present for a long time in history. Here we report on the genetic characterization of G6PD deficiency among inhabitants of one Mediterranean region-the Dalmatian region of south Croatia. We analyzed 24 unrelated G6PD-deficient male subjects. Molecular testing revealed several different mutations: G6PD Cosenza 9, G6PD Mediterranean 4, G6PD Seattle 3, G6PD Union 3, and G6PD Cassano 1. Furthermore, we have identified one novel G6PD variant that we named G6PD Split. This variant is caused by a nucleotide change 1442 C-->G leading to the amino acid substitution 481 Pro-->Arg and is characterized by moderate enzyme deficiency (class III variant). This study reveals a higher prevalence (37.5%) of the Cosenza mutation in the Dalmatian region than anywhere else previously investigated and overall shows the considerable molecular heterogeneity underlining G6PD deficiency that can be observed in Mediterranean populations.