Molecular analysis of hereditary hemolytic anemia due to red cell enzyme anomalies

点击翻译按钮获取中文摘要

We discovered 12 cases of glucose-6-hosphate dehydrogenase deficiency, 3 cases of pyruvate kinase deficiency and 1 case of phosphofructokinase deficiency by the enzymatic analysis of 96 families associated with hereditary non-spherocytic hemolytic anemia.Hexokinase (HK) deficiency is the rare red cell enzymopathy associated with hereditary hemolytic anemia. We discovered a fetus with severe anemia as a first Japanese case of HK deficiency. Mother was hospitalized at 29 weeks of gestation due to intrauterine growth retardation. Ultrasonography showed periventricular leucomalacia of the fetus. Hematological examination showed that the fetus had severe hemolytic anemia : hemoglobin, 3.7g/dl ; reticulocyte, 42.1% ; indirect bilirubin, 5.8mg/dl. Red cel enzyme analysis at 32 weeks of gestation showed that HK activity was decreased to about 15%. Red cell HK activities of the parents were also decreased to about 50% of normal mean value. There was no consanguinity in the family. The affected … More fetus died in utero at 37 weeks of gestation. To elucidated molecular lesion of HK deficiency of the proband, reticulocyte RNA was used for amplify the full-length cDNA for type-I HK (HK-I) by long PCR method. By use of the primer corresponding 5'- and 3'-noncoding sequence, 2.8kb HK-I cDNA was amplified by using RNA from a reticulocyte-rich control ; whereas 2.3kb was obtained from the proband's reticulocyte. Sequence of these short cDNA showed that 2.3kb cDNA lacked exon 5 through 8. To clarify gene abnormalities responsible for these exon skipping, we determined genomic structure of human HK-l gene. The HK-I gene spans about 67kb and had 19 coding exons. Analysis of the genomic sequence showed that the fetus was a homozygote of 9kb intragenic deletion.We discovered a family of red cell enolase deficiency associated with hereditary hemolytic anemia. A Japanese boy was hospitalized due to acute aplastic crisis following parvovirus infection at the age of 8 years. After the recovery from transient erythroid aplasia, chronic hemolytic anemia became evident : hemoglobin, 9.1g/dl ; reticulocyte, 7.7% ; indirect bilirubin, 1.0mg/dl. Red cell enzyme assay demonstrated that the proband had decreased enolase activity : 4.08IU/gHb (normal range 6.04-8.10). The enolase activities of the parents were also decreased : the father, 4.93 ; the mother, 2.83. To elucidated molecular lesion of enolase deficiency, reticulocyte RNA was used for the amplification of the full-length α enolase cDNA by RT-PCR. We elucidated that the proband and his mother had a missense mutation (Arg to His at position 183). Less