Study of the Molecular Defects in Pyruvate Kinase Deficient Patients Affected by Nonspherocytic Hemolytic Anemia

We have examined DNA from fifteen unrelated pyruvate kinase deficient patients with hereditary nonspherocytic hemolytic anemia (HNSHA) for the molecular alterations responsible for the enzyme deficiency. All but 3 of the 30 putative mutations were identified. Fourteen different mutations were found. Nine were missense mutations: 320 T_C, 823 G_C, 1276 C_T, 1376 C_T, 1378 G_A, 1484 C_T, 1529 G_A, 1654 G_A, 1675 C_G; three were nonsense mutations: 603 G_A, 721 G_T, 1501 C_T; one was an insertion at 1574 GGG_GGGG and the other a three nucleotide in-frame deletion 391-392-393 ATC. Eight of these mutations have not been previously described. We also investigated all of the patients for the C/A polymorphism at nt 1705 and the microsatellite ATT repeat in intron 11. All of the mutations that had previously been reported by us (391-393del, 721T, 1484T, 1529A) were found in the context of the same haplotype as the earlier cases, supporting the concept that each may have a single origin.