Molecular and biochemical data on some glucose-6-phosphate dehydrogenase variants from southern Sardinia.

Background: Glucose-6-phosphate dehydrogenase (G6PD; E.C.1.1.1.49) deficiency is the most common human enzymopathy; nearly 400 different biochemical variants of the enzyme have been described. Sardinia is the Italian region with the highest frequency of this defect.
Methods: We examined genomic DNA of 16 subjects with G6PD Mediterranean, 2 with G6PD Athens-like, 1 with G6PD Ferrara 2 (all as biochemically defined).
Results: All G6PD Mediterranean subjects had a C-->T mutation at nucleotide 563 and a C-->T transition at nucleotide 1311; G6PD Athens-like and Ferrara 2 subjects had a G-->C mutation at nucleotide 844 (the same mutation has been found in G6PD Seattle-like).
Conclusions: This study suggests that in Southern Sardinia G6PD mutations are relatively homogeneous and that the results of biochemical characterization studies must be carefully evaluated, because the same mutations might be responsible for different biochemical behavior.