Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Restriction endonuclease mapping of cellular DNA has been used to identify chromosomes that carry the mutant Hb Presbyterian beta-globin genes in a family with individuals heterozygous for this disease. The presence of the polymorphic Hind III restriction site in the G gamma-globin gene and its absence in the A gamma-globin gene were shown to be in phase with the Hb Presbyterian mutation yielding a haplotype constellation that is diagnostic for any further affected offspring.
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PMID:DNA restriction mapping identifies the chromosome carrying the mutant Hb Presbyterian beta-globin gene. 630 49

Previous studies of the Hpa I cleavage site-sickle cell hemoglobin gene linkage in various African populations suggested that the sickle gene arose independently more than once. In the present study we have performed restriction endonuclease haplotype analysis for the beta-globin-like gene cluster from four separate geographic areas in Africa, all of which possess the sickle gene. In Benin (Central West Africa) and Algeria (Arab North Africa) all chromosomes carrying the sickle gene possess an identical haplotype as defined by 11 different polymorphic restriction endonuclease sites within the 60-kilobase region of the beta-globin-like gene cluster. In the Central African Republic (Bantu-speaking Africa) and in Senegal (Atlantic West Africa) a very large proportion of the sickle gene chromosomes were associated with a haplotype specific for each country. Thus, three different haplotypes are shown to be associated with the sickle gene in Africa, and each is present at a very high frequency in geographically separate regions. Since the three haplotypes differ from each other by at least three sites residing both 5' and 3' to a putative hot spot for recombination, it is most likely that the sickle gene arose at least three times on separate preexisting chromosomal haplotypes. This may have implications for a better understanding of the variable nature of the expression of sickle cell anemia, because clinically relevant sequences (for example, gamma-globin gene regulatory sequences responsive to anemia) might be linked polymorphically to these haplotypes.
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PMID:Evidence for the multicentric origin of the sickle cell hemoglobin gene in Africa. 658 11

A previous report demonstrated that endothelial cells have erythropoietin receptors and respond to this hormone with enhanced proliferation. The present study demonstrates the existence of mRNA for erythropoietin receptor in human umbilical vein endothelial cells. We have reverse transcribed mRNA of endothelial cells and then used different PCR primers to amplify erythropoietin receptor target cDNA between exons 5 and 6 as well as 3-5 in addition to an internal standard DNA fragment. Correspondence of size as well as location of restriction endonuclease scission (Ava II) was used in comparing the amplified fragments of human endothelial cell erythropoietin receptor to those of two human erythroleukemia cell lines, OCIM1 and K562. No alpha- or gamma-globin mRNA was detected in endothelial cells but was readily demonstrable in OCIM1 cells. In addition, to determine whether the expression of human erythropoietin receptor on endothelial cells occurs in vivo, sections of umbilical cord and placenta were immunostained with antibodies against the extracellular portion of the receptor; the results showed strong positive staining of the vascular endothelium.
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PMID:Erythropoietin receptor mRNA expression in human endothelial cells. 817 Oct 22

To investigate the molecular basis of severe clinical presentation in sickle cell disease (SCD) patients in Yemen, this study was conducted on 30 Yemeni SCD patients living in Riyadh and attending King Khalid University Hospital. Seven individuals without SCD were used as controls. Haematological parameters, red cell indices, Hb A2 and Hb F levels were estimated and haemoglobin variant were identified on electrophoresis profiling. DNA was extracted from the buffy coat separated from fresh blood samples and was treated with the restriction endonuclease: Xmn I. The fragments generated were separated on electrophoresis, transferred to nitrocellulose and hybridized to a 32P-labelled probe of gamma-globin gene. After extensive washing, two bands, 8.1 kb and 7.0 kb in size, were obtained. The frequency of occurrence of the presence of Xmn I polymorphic site (7.0 kb fragment) and its absence (8.1 kb fragment) were documented. The results in Yemeni SCD patients were compared with the results obtained previously in Saudi Arabs. Of the 30 SCD patients from Yemen 29 had only the 8.1 kb fragment and one had only the 7.0 kb fragment. This gave the frequency of 0.966 for the absence (-) and 0.033 (+) for the presence of Xmn I polymorphic site. This is the same result as that reported earlier for SCD patient from southwestern Saudi Arabia [(-) = 0.966; (+) = 0.033] but is significantly different from that reported in the eastern province [(-) = 0.068; (+) 0.932)] of Saudi Arabia. This paper presents the nature of molecular linkage in SCD patients from Yemen.
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PMID:Xmn I polymorphic site in Yemeni sickle cell disease patients. 1073 37


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