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

A Vietnamese couple were both carriers of alpha-thalessemia-1. The woman had a first pregnancy terminated in the delivery of a hydropic fetus due to homozygous alpha-thalassemia. The couple requested prenatal diagnosis for the second pregnancy. The DNA obtained from cultured amniotic fluid cells was studied pregnancy. The DNA obtained from cultured amniotic fluid cells was studied by hybridization with globin cDNA in solution and on filters (Southern technique). Both analyses demonstrated no alpha-globin structural genes were present. Following termination of the pregnancy, the diagnosis was established by the presence of only hemoglobins Barts (gamma 4) and Portland (zeta 2 gamma 2) in the fetal blood.
 ...
PMID:Prenatal diagnosis of homozygous alpha-thalassemia. 43 Jul 15

alpha-Thalassemia hydrops fetalis is a common disorder in Taiwan. The condition causes perinatal death and many maternal obstetrical complications. In order to determine the molecular defects of this condition in Chinese, 87 unrelated families with this disorder were collected in the past 4 years. The molecular defects were studied by Southern blotting and DNA hybridization with phi zeta 1-globin gene and LO (a 0.4 kb BamHI/EcoRI fragment in the 5' flanking region of the zeta 2-globin gene) probes. Eighty-one (93.1%) fetuses had homozygous Southeast Asian deletion (- -SEA/- -SEA). Five (5.7%) fetuses were compound heterozygotes for the Southeast Asian deletion and Thailand deletion (- -SEA/- -THAI). The remaining fetus was a compound heterozygote for the Southeast Asian deletion and an uncharacterized nondeletional defect (- -SEA/(alpha alpha)Th). The molecular defects of alpha-thalassemia hydrops fetalis in Chinese are heterogeneous. This fact has important implications for genetic counseling and prenatal diagnosis.
 ...
PMID:Molecular characterization of severe alpha-thalassemias causing hydrops fetalis in Taiwan. 186 84

Reversed-phase high-performance liquid chromatography (RP-HPLC) using the large-pore Vydac C4 column has been used to detect and quantitate the embryonic zeta chain in blood samples of normal babies and of newborns with varying degrees of alpha chain deficiencies. The zeta chain eluted at the end of the chromatogram at about 130 min using a modified and extended gradient. Its identity was confirmed by structural analysis of zeta chain isolated from a blood sample of a fetus without active alpha globin genes, i.e. with hydrops fetalis (--/--). The quantity of zeta in normal babies is less than 0.7% [% of (alpha + zeta)] and is dependent upon the maturity of the baby as it was only present in babies with low levels of beta chain or hemoglobin (Hb) A. The presence of a zeta globin gene deletion [A. E. Felice et al., Hum. Genet., 73 (1986) 221; and P. Winichagoon et al., Nucleic Acids Res., 10 (1982) 5853] did not affect the level of zeta in the newborn. All babies with an alpha-thalassemia-2 heterozygosity, i.e. with three active alpha globin genes or -alpha/alpha alpha, had zeta in a range of 0.1-0.9%; again the level showed a negative correlation with that of the beta chain. Newborns with an alpha-thalassemia-2 homozygosity or -alpha/-alpha had a varying level of zeta of 0.3-2.3%, which did not correlate with the level of beta, suggesting that zeta chain production persists after birth in this condition. Macrochromatographic analyses in combination with RP-HPLC indicated that the zeta chain is present as zeta 2 gamma 2 or Hb Portland-I, as expected.
 ...
PMID:Detection of the embryonic zeta chain in blood from newborn babies by reversed-phase high-performance liquid chromatography. 244 82

Details are presented of analyses of hemoglobins in blood samples from four newborn babies with hydrops fetalis using reversed phase and anion exchange high performance liquid chromatographic methodology. Three were homozygous for the alpha-thalassemia-1 (SEA) deletion, and one was a compound heterozygote for the same deletion and the larger alpha-thalassemia-1 (Fil) deletion. All four babies had beta, G gamma, A gamma, and zeta chains; these chains were present in Hb Bart's or gamma 4, Hb Portland-I (zeta 2 gamma 2), and Hb Portland-II (zeta 2 beta 2). Hb H (beta 4) could not be detected. The level of zeta was directly related to the level of beta and, thus, the fetal age. A lower level of zeta chain was present in the baby with the compound heterozygosity because the large deletion (Fil) on one chromosome included the zeta and psi zeta genes. Circulating red cells, i.e. reticulocytes and nucleated red cells, were unable to synthesize zeta chains, indicating that this capability must have ceased a few months prior to birth. Quantitative data obtained by chromatographic procedures were greatly influenced by the condition of the blood sample and the way it was stored. Hb Portland-II (zeta 2 beta 2) and Hb Bart's (gamma 4) are rather unstable when a red cell lysate is stored at 4 degrees C; this is in contrast to Hb Portland-I (zeta 2 gamma 2) which appears to be stable. Samples can be stored as washed red cells or red cell lysates at -70 degrees C.
 ...
PMID:The types of hemoglobins and globin chains in hydrops fetalis. 263 68

We describe the first known association between autosomal dominant polycystic kidney disease (ADPKD) and alpha-4.2 thalassemia in a Caucasian family. Linkage studies have been carried out using two probes (3'HVR and 24-1) linked to ADPKD on locus PKD1 and two probes (alpha 1-PstI and BamH-I/EcoRI-zeta 2 fragment) allowing detection of alpha-thalassemia with either a 3.7-kb deletion or a 4.2-kb deletion. Our results show that to avoid misinterpretation it is important to investigate the occurrence of an alpha-gene deletion when polymorphisms situated in the alpha-globin locus are used for linkage studies on ADPKD. The studied family is one of the rare cases of leftward deletional thalassemia described in a non-Asian population.
 ...
PMID:Autosomal dominant polycystic kidney disease and alpha -4.2 thalassemia in a Caucasian family. 276 79

In screening families for alpha-thalassemia (thal) by the Southern blot technique, several Laotian families were found which had anomalous zeta-globin haplotypes. The zeta-globin genes encode alpha-like embryonic hemoglobin subunits in the alpha-globin multigene complex on chromosome 16. There are normally two zeta-globin genes in this cluster: 5' zeta 2 and 3' psi zeta 1. In our study, six individuals in three families had triple zeta-globin genes. Another family revealed a novel quadruple zeta-globin arrangement. Two aberrant fragments were seen in Eco R1, Bam H1, Bgl II and Hind III digests using a zeta-globin gene probe. These anomalous bands were in the integral 10 kb range consistent with duplication of the zeta-globin region. This haplotype interpretation was confirmed by Southern blot analyses using double digestions hybridized to a cDNA zeta-gene probe, and Pvu II digests probed with a 5'-psi zeta 1 intergenic fragment. Proposed mechanisms of recombination and implications of this novel arrangement are discussed.
 ...
PMID:Alpha-thalassemia screening reveals quadruple zeta-globin genes in a Laotian family. 320 96

A new alpha thalassemia defect has been detected in the South African population. Restriction mapping of the alpha globin gene cluster in affected individuals has established that the defect is associated with the removal of 22.8-23.7 kb of DNA, including the psi zeta 1, psi alpha 1, psi alpha 2, alpha 2 and alpha 1 globin genes. The 5' endpoint of the deletion has been localized between the zeta 2 and psi zeta 1 globin genes, and the 3' endpoint lies 4-5 kb 3' to the alpha 1 globin gene. We have called the deletion - -SA in order to distinguish it from alpha zero thalassaemia defects described in other populations.
 ...
PMID:Characterization of a new alpha zero thalassaemia defect in the South African population. 366 10

The amino acid compositions of tryptic peptides and cyanogen bromide fragments of the purified zeta chain of Hb Portland I (zeta 2 gamma 2) and Hb Portland II (zeta 2 beta 2) have been determined. The hemoglobins were obtained from blood from neonates with hydrops fetalis due to homozygous alpha-thalassemia. The globin chains, tryptic peptides and cyanogen bromide fragments were all separated by reverse phase high performance liquid chromatography (HPLC). Several different types of C-18 columns were used with two different developer systems. The tryptic peptides of aminoethylated zeta chain were separated using an ammonium acetate-acetonitrile gradient. An aqueous trifuoroacetic acid-1-propanol developer gradient was used for the separation of cyanogen bromide fragments. Of the seventeen tryptic peptides obtained, two (zeta T10a and zeta T10b) resulted from the unusual cleavage of a Tyr-Ile peptide bond. This was observed even when using TPCK treated trypsin. From this study and results of others, it can be deduced that trypsin will hydrolyze the Tyr-X bond provided either Ala or Ile is bonded to the N-terminal side of Tyr and Ile, Leu, or Gly is bonded to the C-terminal side of the Tyr residue.
 ...
PMID:Separation of the tryptic peptides and cyanogen bromide fragments of the human embryonic zeta chains of hemoglobin in Portland I and II by reverse phase high performance liquid chromatography. 650 Sep 86

Two types of embryonic hemoglobins (Hb) containing zeta chains have been identified in the blood of several neonates of Chinese origin with homozygous alpha-thalassemia. In addition to Hb Portland I (zeta 2 gamma 2) which was previously reported, another embryonic hemoglobin has been detected and found to contain zeta chains and beta chains. It is being designated Hb Portland II and has the formula (zeta 2 beta 2). It has a mobility slightly slower than that of Hb A on starch gel electrophoresis at pH 8.6 and has been found in the hemolysates of blood of some but not all hydropic infants. Another component with a mobility faster than that of Hb A2 on starch gel has been isolated from the blood of some hydropic neonates. This latter component is postulated to be zeta 2 delta 2. The occurrence of Hb Portland I and Hb Portland II in these hydropic neonates is consistent with the hypothesis that, in the absence of normal alpha chain production, zeta chains are continued to be produced at later states of development than normal and form tetramers with each of the beta-like globin chains. Because Hb Portland II has not been found in blood from all hydropic neonates, we postulate that the presence of this hemoglobin in these fetuses may be correlated with the gestational age of the fetus at the time of birth.
 ...
PMID:Human hemoglobin Portland II (zeta 2 beta 2). Isolation and characterization of Portland hemoglobin components and their constituent globin chains. 653 34

Restriction endonuclease mapping with alpha and zeta-globin gene probes showed differences between the alpha-thalassemia-1 (alpha-thal-1) condition in two patients with HbH disease. One patient had the rare black type of alpha-thal-1 together with alpha-thal-2 and HbS heterozygosities. The second patient was a Laotian child with HbE, Hb Constant Spring (alpha-thal-2), and alpha-thal-1 heterozygosities. The diagnoses were based on clinical, hematologic, and biochemical data. Whereas DNA fragments hybridizing to a zeta-probe were obtained from the Laotian type of alpha-thal-1, neither alpha nor zeta-gene fragments could be identified deriving from the black type of alpha-thal-1. Therefore, the black type of alpha-thal-1 is associated with a deletion of the entire zeta 2-psi zeta-psi alpha-alpha 2-alpha 1 gene complex and can be considered a zeta alpha-thal-1. It is likely that homozygosity for such a condition will lead to embryonic wastage, explaining the absence of hydrops fetalis in blacks.
 ...
PMID:The rare alpha-thalassemia-1 of blacks is a zeta alpha-thalassemia-1 associated with deletion of all alpha- and zeta-globin genes. 671 99


1 2 Next >>