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, 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.