Hereditary myeloperoxidase (MPO) deficiency (MPOD) is the most common neutrophil biochemical defect, and is characterized by a lack of peroxidase activity. In order to extend the epidemiological studies on hereditary MPOD in Italy, a population screening was carried out to detect mutations in the MPO gene. Of approximately 40,000 individuals analyzed, seven partial and eight total MPO-deficient subjects were identified. The genetic characterization of the subjects showed the presence of three already-known mutations (c.752T>C, c.1705C>T, and c.1566_1579del14) and six novel mutations: four missense mutations (c.995C>T, c.1112A>G, c.1715T>G, and c.1927T>C), then a deletion of an adenine within exon 3 (c.325delA) and a mutation within the 3' splice site of intron 11 (c.2031-2A>C). The novel missense mutations cause the substitution of the residues p.A332V, p.D371G, p.L572W, and p.W643R, respectively, and the potential structural changes are discussed.
