Analysis and prenatal diagnosis of PKLR gene mutations in a family with pyruvate kinase deficiency / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of genetic and prenatal diagnosis for a family affected with pyruvate kinase deficiency (PKD).</p><p><b>METHODS</b>Targeted sequence capture and high-throughput sequencing technology was used to detect the exons and exon-intron boundaries of the PKLR gene in a clinically suspected PKD patient. Meanwhile, the genotype of the pedigree was validated by Sanger sequencing. Prenatal genetic diagnosis was performed by amniotic fluid sampling after genotype of the mother of the proband was determined.</p><p><b>RESULTS</b>The proband was found to harbor double heterozygous mutations, c.661G>A (Asp221Asn) and c.1528C>T (Arg510Ter), which resulted in amino acid substitution Asp221Asn and Arg510Ter. Such mutations were confirmed by Sanger sequencing. The mother and father of the proband were detected to have respectively carried c.1528C>T (Arg510Ter) and c.661G>A (Asp221Asn) mutation. The fetus was found to have carried the same mutations as the proband. Following selected abortion, analysis of fetal tissue was consistent with the result of prenatal diagnosis.</p><p><b>CONCLUSION</b>The compound mutations of c.661G>A and c.1528C>T of PKLR gene probably underlie the PKD in the family. Prenatal diagnosis of the mutations analysis can facilitate detection of affected fetus in time.</p>

Glucose-6-phosphate Dehydrogenase Deficiency / 임상소아혈액종양

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme disorder. There are more than 400 million people worldwide with G6PD deficiency, and its distribution is similar to that of malaria. G6PD deficiency is an X-linked recessive disorder. Most patients with G6PD deficiency may be asymptomatic throughout their lives. They may present as neonatal jaundice, or acute and chronic hemolysis. The most important point in the management of G6PD deficiency is to avoid oxidative stress. The prevalence of G6PD deficiency in Korea is about 0.9%. However, a nationwide survey has revealed that the number of patients with enzymopathy is increasing. Immigration of different ethnicities into Korea, and the rise of interracial marriages will likely lead to an increase in the number of patients with G6PD deficiency.

Glucose-6-phosphate Dehydrogenase Deficiency / 임상소아혈액종양

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme disorder. There are more than 400 million people worldwide with G6PD deficiency, and its distribution is similar to that of malaria. G6PD deficiency is an X-linked recessive disorder. Most patients with G6PD deficiency may be asymptomatic throughout their lives. They may present as neonatal jaundice, or acute and chronic hemolysis. The most important point in the management of G6PD deficiency is to avoid oxidative stress. The prevalence of G6PD deficiency in Korea is about 0.9%. However, a nationwide survey has revealed that the number of patients with enzymopathy is increasing. Immigration of different ethnicities into Korea, and the rise of interracial marriages will likely lead to an increase in the number of patients with G6PD deficiency.

A PKLR Gene Novel Complex Mutation in Erythrocyte Pyruvate Kinase Deficiency Detected by Targeted Sequence Capture and Next Generation Sequencing / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the molecular mechanism of erythrocyte pyruvate kinase deficiency (PKD).</p><p><b>METHODS</b>Targeted sequence capture and next-generation sequencing (NGS) were used to detect the regions of exon and exon-intron boundarie of PKLR gene in a clinical suspected PKD patient. The protein function of mutant gene was forecasted by the SIFT and PolyPhen-2 databank, after the mutation of PKLR gene in the patient was detected by the NGS technology, its genotype was confirmed by Sanger sequencing.</p><p><b>RESULTS</b>The patient was found to have peculiar double heterozygous mutations: 661 G>A (Asp221Asn) of exon 5 and 1528 C>T (Arg510Ter) of exon 10, resulting in amino acid substitution Asp221Asn and Arg510Ter, these mutations were also further confirmed by Sanger sequencing. The complex mutations were infrequent and each of them was able to cause diseases.</p><p><b>CONCLUSION</b>The complex mutations of both 661 G>A and 1528 C>T of PKLR gene are the molecular mechanism of PKD. Simultaneous existance of above-mentioned complex mutations in PDK patient was never been previously reported at home and abroad.</p>

Analysis of a pyruvate kinase deficiency consanguineous pedigree caused by Ile314Thr homozygous mutation / 中华血液学杂志

<p><b>OBJECTIVE</b>To screen potential mutation and explore the underlying mechanism for a consanguineous pedigree featuring pyruvate kinase (PK) deficiency.</p><p><b>METHODS</b>The red blood cell pyruvate kinase activities of all family members were detected. All the exons and intron-exon boundaries of the PKLR gene for the proband were amplified and analyzed by direct sequencing. Restriction endonuclease enzymes were used to identify the presence of mutations of all family members.</p><p><b>RESULTS</b>The pyruvate kinase activities were 5.89 U/g Hb in the proband, 3.45, 6.54, 8.87, 7.89, 9.32 U/g Hb in his younger sister, father, mother, grandmother and elder aunt, respectively. The homozygous missense mutation of T>C transition at position 941 in exon 7 of PKLR gene resulted to a Ile314Thr substitution in the proband, and mutant alleles were identified at the level of RNA transcript by cDNA sequence analysis. His younger sister was also homozygous for Ile314Thr. Heterozygosity for Ile314Thr was confirmed in his grandmother, parents and elder aunt.</p><p><b>CONCLUSION</b>Ile314Thr homozygous missense mutation in exon 7 of PKLR is the molecular mechanism of pyruvate kinase deficiency in this family.</p>

First-trimester prenatal diagnosis of pyruvate kinase deficiency in an Indian family with the pyruvate kinase-Amish mutation

Pyruvate kinase (PK) deficiency is a rare red cell glycolytic enzymopathy. The purpose of the present investigation was to offer prenatal diagnosis for PK deficiency to a couple who had a previous child with severe enzyme deficiency and congenital non-spherocytic hemolytic anemia. PK deficiency was identified in the family by assaying the enzyme activity in red cells. Chorionic villus sampling was performed in an 11-week gestation and the mutation was located in exon 10 of the PKLR gene characterized by polymerase chain reaction and using restriction endonuclease digestion with the MspI enzyme, which was confirmed by DNA sequencing on the ABI 310 DNA sequencer. Both the parents were heterozygous for the 1436G-->A [479 Arg-->His] mutation in exon 10 and the proband was homozygous for this mutation. The fetus was also heterozygous for this mutation and the pregnancy was continued. Prenatal diagnosis allowed the parents with a severely affected child with PK deficiency to have the reproductive choice of having the fetus tested in a subsequent pregnancy.

Anemia hemolítica no esferocítica (AHCNE) por deficiencia de piruvato quinasa: informe del segundo caso en Costa Rica / Nonspherocytic hemolytic anemia to piruvate kinase deficiency: Inform of second case in Costa Rica

Se describe el segundo caso hallado en Costa Rica de anemia hemolítica crónica no esferocítica (AHCNE) por deficiencia de un piruvato quinasa, en una niña de 12 años de edad. Del estudio familiar, inicialmente orientado en su diagnóstico por una prueba positiva del cianuro ascorbato, se sugiere el posible caracter doble heterocigoto de la deficiencia en la paciente, eventualmente dada por dos variables enzimáticas por cooperación negativa

Gd(-) Carapicuiba, a rare glucose-6 phosphate dehydrogenase variant associated with moderate enzyme deficiency and chronic hemolysis

A 27 year old Brazilian male of both Portuguese and Spanish origin presenting nonspherocytic chronic hemolytic anemia was found to have a rare glucose-6-phosphate dehydrogenase variant herein named Gd(-) Carapicuiba. The red blood cell enzyme variant is characterized by a moderate enzyme deficiency (47%), high Km for its substrates G6P and NADP, decreased activity against deamino-NADP, increased Ki for NADPH and decreased heat stability. The clinical signs of the patient are probably related to these properties of the enzyme variant

A Case of Congenital Nonspherocytic Hemolytic Anemia

No abstract available.