Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rarity of hemoglobin (Hb) H disease in combination with sickle trait may be due in part to the absence of actual Hb H in individuals who, nonetheless, have inherited the deletion of three alpha-globin genes. We describe here a boy with persistent microcytic, hypochromic anemia despite adequate iron stores, who exhibited splenomegaly with a normal reticulocyte count and only rare inclusions in circulating erythrocytes. Starch gel electrophoresis and isoelectric focusing at age 5 yr showed 21% Hb S, persistent Hb Bart's, but no Hb H. Recticulocyte alpha/non-alpha globin chain synthesis ratio was 0.58 at age 5. The mother (Asian) had laboratory evidence of alpha-thalassemia trait and the father (Black) had sickle trait. The nature of alpha-thalassemia in this patient was investigated both by liquid hybridization and by the Southern method of gene mapping, in which DNA is digested with restriction endonucleases and the DNA fragments that contained the alpha-globin structural gene identified by hybridization with complementary DNA. The patient had only one alpha-globin structural gene, located in a DNA fragment shorter than that found in normal or alpha-thalassemia trait individuals, but similar to that present in other patients with Hb H disease. Morphologic studies of bone marrow by light and electron microscopy revealed erythroid hyperplasia with inclusions in polychromatic and orthochromatic erythroblasts, suggesting early precipitation of an unstable hemoglobin. The lack of demonstrable Hb H may be the result of both diminished amounts of beta(A) available for Hb H formation (since one beta-globin gene is beta(S)) and the greater affinity of alpha-chains for beta(A) than beta(S)-globin chains leading to the formation of relatively more Hb A than Hb S. The presence of a beta(S) gene may thus modify the usual clinical expression of Hb H disease.
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PMID:Modification of hemoglobin H disease by sickle trait. 47 66

Blood specimens were obtained from 281 inhabitants of an Eti-Turk village with a population of about 500. Starch gel (pH 8.6) and agar gel (pH 6.45) electrophoresis were performed in 279 of the specimens. Hb S was present in 105 partially interrelated persons (37.36%), three of whom had sickle-cell anaemia. Hb E was detected in 5 persons (1.79%), one of whom was a double heterozygote for Hb S and Hb E. One Hb S+alpha-thalassaemia and 7 Hb S with elevated Hb A'2 combinations were found. The beta-thalassaemia gene prevalence was 0.0377. Hb A2 was found in 4 persons (1.42%), and Hb F was slightly increased in 37 (22.3%) persons with a normal haemoglobin picture. Erythrocyte G-6-PD deficiency was 10% among males.
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PMID:Haemoglobinopathy survey in an Eti-Turk village. 115 Feb 94

An American Negro woman was found to have HbH disease in association with HbG Philadelphia (alpha68-asn leads to lys). Starch gel electrophoresis failed to reveal the presence of any HbA or HbA2 and studies of globin chain synthesis indicated absence of alphaA production. The alphaG/beta synthesis ratio was 0.63. The woman's son and her two half-sibs had alpha-thalassaemia trait with no HbH and alpha/beta synthesis ratios of 0.84, 0.84 and 0.76. The data indicate that there is no functioning alphaA gene linked to the alphaG gene. The absence of alphaA synthesis by the propositus also indicates that the alpha-thalssaemia gene trans to the alphaG gene completely suppresses alpha chain production, the first evidence for such a gene in Negroes.
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PMID:The interaction of alpha-thalassaemia and haemoglobin G Philadelphia. 124 89

EF Bart's disease is an uncommon form of thalassaemia intermedia resulting from the co-inheritance of alpha-thalassaemia and haemoglobin E in the same subject. Starch-gel electrophoresis revealed two phenotypes in 19 patients with EF Bart's. 16 patients had Hbs CS + E + F + Bart's and the remainder had Hbs E + F + Bart's. DNA mapping and haemoglobin electrophoresis indicated that there are four genotypes, involving 5 abnormal globin genes, responsible for this thalassaemia syndrome.
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PMID:EF Bart's disease: interaction of the abnormal alpha- and beta-globin genes. 334 62