MOLECULAR STUDY OF PYRUVATE-KINASE DEFICIENT PATIENTS WITH HEREDITARYNONSPHEROCYTIC HEMOLYTIC-ANEMIA

DNA analysis was performed on 30 unrelated patients with hereditary no nspherocytic hemolytic anemia(HNSHA) who had been found to be pyruvate kinase (PK) deficient by enzyme assay, 19 different mutations were id entified among 58 of the 60 alleles at risk, 13 of these were missense mutations that caused single amino acid changes, Included were the fo llowing nucleotide substitutions: 401A, 464C, 993A, 1022C, 1076A, 1178 G, 1179A, 1373A, 1378A, 1456T, 1493A, 1529A, The remaining six mutatio ns were as follows: two nonsense mutations, 721T and 808T; a nucleotid e deletion, 307C; a nucleotide insertion, 1089GG; a three nucleotide i n frame deletion, 391-392-393 and a deletion of 1149 bp from the PKLR gene that resulted in the loss of exon 11, All the patients were studi ed for two polymorphic sites, nucleotide (nt) 1705 A/C and a microsate llite in intron 11, to better understand the origin of the mutations, The 1529A mutation, which is the most common mutation in the European population, was found in 25 alleles, With a single exception this muta tion was in linkage disequilibrium with both of the polymorphic marker s, i.e., found with 1705C and 14 repeats in the microsatellite. This f inding is consistent with a single origin of this common mutation, Oth er mutations occurring more than once were of much lower frequency tha n the 1529A mutation.