Evaluation of beta-thalassemia in the fetus through cffDNA with multiple polymorphisms as a haplotype in the beta-globin gene

2020 ◽  
Vol 27 (4) ◽  
pp. 243-252
Author(s):  
Nadia Mirzaei Gisomi ◽  
Gholamreza Javadi ◽  
Shohre Zare Karizi ◽  
Mohammad Miryounesi ◽  
Parvaneh Keshavarz
Keyword(s):  
Globin Gene ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Beta Globin Gene

scholarly journals The inactive beta globin gene on a gamma delta beta thalassemia chromosome has a normal structure and functions normally in vitro

Blood ◽  
1988 ◽  
Vol 71 (3) ◽  
pp. 766-770
Author(s):  
PT Curtin ◽  
YW Kan
Keyword(s):  
Globin Gene ◽  
Large Deletion ◽  
Beta Thalassemia ◽  
Ribonuclease Protection Assay ◽  
Beta Globin ◽  
Gamma Delta ◽  
Beta Globin Gene ◽  
Thalassemia Minor

We have previously described an English family with gamma delta beta- thalassemia in which a large deletion stops 25 kilobases (kb) upstream from the beta-globin gene locus, and yet the beta-globin gene is inactive in vivo. Affected family members had a beta-thalassemia minor phenotype with a normal hemoglobin A2 level. Gene mapping showed that these subjects were heterozygous for a chromosome bearing a large deletion that began in the G gamma-globin gene, extended through the epsilon-globin gene, and continued upstream for at least 75 kb. The A gamma-, delta-, and beta-globin gene loci on this chromosome were intact. To examine the possibility that an additional defect was present in the beta-globin gene, we cloned, sequenced, and examined the expression of the beta-globin gene from the affected chromosome. No mutation was found in the beta-globin gene sequence from 990 base-pairs 5′ to the cap site to 350 basepairs 3′ to the polyadenylation signal. The gene was subcloned into an expression vector and introduced into HeLa cells. Analysis of RNA derived from these cells, using a ribonuclease protection assay, revealed qualitatively and quantitatively normal transcription. Thus a structurally and functionally normal beta-globin gene is inactive in the presence of a large deletion more than 25 kb upstream. The loss of beta-globin gene function may be due to disturbance of chromatin conformation caused by the deletion or may be the result of loss of upstream sequences that are necessary for beta-globin gene expression in vivo.

scholarly journals Molecular analysis of Japanese delta beta-thalassemia

Blood ◽  
1988 ◽  
Vol 72 (5) ◽  
pp. 1771-1776
Author(s):  
S Shiokawa ◽  
H Yamada ◽  
Y Takihara ◽  
E Matsunaga ◽  
Y Ohba ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
Beta Thalassemia ◽  
Globin Genes ◽  
Beta Globin ◽  
Beta Globin Gene ◽  
Gamma Globin ◽  
Large Deletions ◽  
Deletion Junction

A DNA fragment containing the deletion junction region from a Japanese individual with homozygous delta beta-thalassemia has been cloned. A clone containing the normal DNA surrounding the 3′ breakpoint of this deletion and a clone carrying the G gamma- and A gamma-globin genes of this patient were also isolated. Sequences of the deletion junction and both gamma-globin genes were determined. A comparison of these sequences with previously determined sequences of the normal counterparts revealed that the 5′ breakpoint is located between 2,134 and 2,137 base pairs (bp) 3′ to the polyA site of the A gamma-globin gene, the 5′ breakpoint is located just downstream of the 3′ border of the fetal gamma-globin duplication unit, and no molecular defects are evident within the gamma-globin gene region. A comparison between the sequences of the normal DNA surrounding the 3′ breakpoint and the normal DNA surrounding the 5′ breakpoint shows that deletion is the result of a nonhomologous recombination event. There are A+T-rich stretches near the 5′ and 3′ breakpoints in the normal DNA, and a portion of an Aly repeat is located in the region 3′ to the 3′ breakpoint. Southern blot analysis using probes 3′ to the beta-globin gene showed that the deletion extends in the 3′ direction further than any other deletions associated with delta beta-thalassemia and hereditary persistence of fetal hemoglobin (HPFH) heretofore reported. These results are discussed in terms of the mechanism generating large deletions in mammalian cells and three models for the regulation of gamma-globin and beta-globin gene expression in humans.

scholarly journals A novel mutation in the TATA box in a Japanese patient with beta +- thalassemia

Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 547-550 ◽  
Author(s):  
Y Takihara ◽  
T Nakamura ◽  
H Yamada ◽  
Y Takagi ◽  
Y Fukumaki
Keyword(s):  
Novel Mutation ◽  
Globin Gene ◽  
Japanese Woman ◽  
Tata Box ◽  
Proximal Promoter ◽  
Base Substitution ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Beta Globin Gene

Abstract A single base substitution (A-G) at position -31 within the highly conserved proximal promoter element, the TATA box, was identified in the beta-globin gene cloned from a Japanese woman with beta +- thalassemia. It appears that she is homozygous for this specific allele, as determined by haplotype analysis using seven different polymorphic sites in the beta-globin gene cluster. Transient expression of the mutant gene in COS cells revealed a 45% reduction in beta-globin RNA production, relative to normal. These results establish the functional significance of the second base of the TATA box for in vivo transcription of the human beta-globin gene.

scholarly journals An approximately 300 bp deletion involving part of the 5' beta-globin gene region is observed in members of a Turkish family with beta- thalassemia

Blood ◽  
1987 ◽  
Vol 70 (2) ◽  
pp. 583-586 ◽  
Author(s):  
JC Diaz-Chico ◽  
KG Yang ◽  
A Kutlar ◽  
AL Reese ◽  
M Aksoy ◽  
...  
Keyword(s):  
Promoter Region ◽  
Genomic Dna ◽  
Restriction Site ◽  
Globin Gene ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Promoter Sequences ◽  
Beta Globin Gene ◽  
Turkish Family ◽  
Thalassemia Trait

Abstract Detailed gene mapping analyses of genomic DNA from two Turkish subjects with a beta-thalassemia trait demonstrated an approximately 300 bp deletion, which is located between the Rsa I restriction site 128 bp 5′ to the Cap site and the Acc I restriction site 284 bp 3′ to the same Cap site; it includes the 5′ beta promoter region, the first exon, and (part of) the IVS-I. Heterozygotes for this and two other beta- thalassemia types, which are also caused by deletions involving 5′ beta promoter sequences, appear to have higher hemoglobin (Hb) A2 levels, perhaps because the loss of this promoter results in an increased transcription of the delta globin gene, as delta and beta promoters may be influenced by the same enhancing sequences 3′ to the beta globin gene.

scholarly journals Observations on the levels of Hb A2 in patients with different beta- thalassemia mutations and a delta chain variant

Blood ◽  
1990 ◽  
Vol 76 (6) ◽  
pp. 1246-1249 ◽  
Author(s):  
JF Codrington ◽  
HW Li ◽  
F Kutlar ◽  
LH Gu ◽  
M Ramachandran ◽  
...  
Keyword(s):  
Promoter Activity ◽  
Globin Gene ◽  
Gene Promoter ◽  
General Mechanism ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Beta Chain ◽  
Beta Globin Gene ◽  
In Trans ◽  
In Cis

Abstract Hb A2 and its variant B2 (alpha 2 delta 2(16)(A13)Gly----Arg) were quantitated in the blood of subjects with three different types of beta- thalassemia and with the delta-B2 anomaly in cis or in trans to the beta-thalassemia determinant. In one family, the delta-B2 mutation was in cis to a newly discovered codon 47 (+A) frameshift. The levels of Hbs A2 and B2 were nearly the same and approximately 70% higher than those in simple Hb B2 heterozygotes. In two additional families, the delta-B2 variant was in trans to either a deletional beta-thalassemia (1,393 bp) involving part of the beta-globin gene and part of the beta- globin gene promoter, or to the -88 C----T promoter mutation. In both instances, the Hb B2 level was increased by approximately 80%, but the Hb A2 level was increased by approximately 270% and 200%, respectively. These data indicate two mechanisms that will cause an increase in delta chain production. One is consistent with a general mechanism concerning the relative excess of alpha chains in beta chain deficiencies which will combine with delta chains to form variable levels of Hb A2 dependent on the severity of the beta chain deficiency. The second concerns the loss of beta-globin gene promoter activity, perhaps by an absence of (or decreased) binding of specific protein(s) to this segment of DNA and a concomitant increase in delta-globin gene promoter activity in cis.

scholarly journals A novel basis for delta beta-thalassemia in a Chinese family

Blood ◽  
1986 ◽  
Vol 68 (5) ◽  
pp. 1108-1113 ◽  
Author(s):  
GF Atweh ◽  
DE Zhu ◽  
BG Forget
Keyword(s):  
Gene Cluster ◽  
Globin Gene ◽  
Beta Thalassemia ◽  
Chinese Family ◽  
Compound Heterozygous ◽  
Beta Globin ◽  
Hemoglobin F ◽  
Beta Globin Gene ◽  
Globin Gene Cluster ◽  
Alpha Beta

Abstract We have studied a Chinese family in which beta-thalassemia and delta beta-thalassemia were found in simple and compound heterozygous states. The delta beta-thalassemia heterozygote (the mother) had 22.3% hemoglobin F, of which 40% was G gamma and 60% A gamma; globin chain studies showed an alpha/beta + gamma ratio of 1.36. The compound heterozygote for delta beta-thalassemia and beta-thalassemia (the child) had the clinical picture of thalassemia intermedia and an alpha/beta + gamma ratio of 4.44. Gene mapping studies were performed using DNA from the affected child. Seventy kilobases of DNA in the beta- globin gene cluster starting upstream from the epsilon-globin gene and ending downstream from the beta-globin gene were mapped, and no detectable deletions or rearrangements were detected. In addition, heterozygosity was detected at multiple polymorphic restriction sites in and 3′ to the beta-globin gene, which excludes the possibility of a deletion of the entire beta-globin gene cluster. This is the first example of a nondeletion delta beta-thalassemia associated with increased expression of both G gamma and A gamma genes.

scholarly journals Molecular analysis of beta zero-thalassemia intermedia in Sardinia

Blood ◽  
1989 ◽  
Vol 74 (2) ◽  
pp. 823-827 ◽  
Author(s):  
R Galanello ◽  
E Dessi ◽  
MA Melis ◽  
M Addis ◽  
MA Sanna ◽  
...  
Keyword(s):  
Nonsense Mutation ◽  
Frameshift Mutation ◽  
Globin Gene ◽  
Thalassemia Major ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Mild Phenotype ◽  
Beta Globin Gene ◽  
Alpha Thalassemia

Abstract In this study we have carried out alpha- and beta-globin gene analysis and defined the beta-globin gene polymorphisms in a group of patients with thalassemia intermedia of Sardinian descent. A group of patients (109) with thalassemia major of the same origin served as control. Characterization of the beta-thalassemia mutation showed either a frameshift mutation at codon 6 or a codon 39 nonsense mutation. We found that homozygotes for the frameshift mutation at codon 6 or compound heterozygotes for this mutation and for the codon 39 nonsense mutation develop thalassemia intermedia more frequently than thalassemia major. The frameshift mutation at codon 6 was associated with haplotype IX that contains the C-T change at position -158 5′ to the G gamma globin gene implicated in high gamma chain production and thus the mild phenotype. In patients' homozygotes for codon 39 nonsense mutation, those with thalassemia intermedia more frequently had the two- gene deletion form of alpha-thalassemia, or functional loss of the alpha 2 gene as compared with those with thalassemia major. In a few siblings with thalassemia major and intermedia, the thalassemia intermedia syndrome correlated with the presence of the -alpha/-alpha genotype. No cause for the mild phenotype was detected in the majority of patients who had not inherited either haplotype IX or alpha- thalassemia.

scholarly journals Molecular analysis of Japanese delta beta-thalassemia

Blood ◽  
1988 ◽  
Vol 72 (5) ◽  
pp. 1771-1776 ◽  
Author(s):  
S Shiokawa ◽  
H Yamada ◽  
Y Takihara ◽  
E Matsunaga ◽  
Y Ohba ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
Beta Thalassemia ◽  
Globin Genes ◽  
Beta Globin ◽  
Beta Globin Gene ◽  
Gamma Globin ◽  
Large Deletions ◽  
Deletion Junction

Abstract A DNA fragment containing the deletion junction region from a Japanese individual with homozygous delta beta-thalassemia has been cloned. A clone containing the normal DNA surrounding the 3′ breakpoint of this deletion and a clone carrying the G gamma- and A gamma-globin genes of this patient were also isolated. Sequences of the deletion junction and both gamma-globin genes were determined. A comparison of these sequences with previously determined sequences of the normal counterparts revealed that the 5′ breakpoint is located between 2,134 and 2,137 base pairs (bp) 3′ to the polyA site of the A gamma-globin gene, the 5′ breakpoint is located just downstream of the 3′ border of the fetal gamma-globin duplication unit, and no molecular defects are evident within the gamma-globin gene region. A comparison between the sequences of the normal DNA surrounding the 3′ breakpoint and the normal DNA surrounding the 5′ breakpoint shows that deletion is the result of a nonhomologous recombination event. There are A+T-rich stretches near the 5′ and 3′ breakpoints in the normal DNA, and a portion of an Aly repeat is located in the region 3′ to the 3′ breakpoint. Southern blot analysis using probes 3′ to the beta-globin gene showed that the deletion extends in the 3′ direction further than any other deletions associated with delta beta-thalassemia and hereditary persistence of fetal hemoglobin (HPFH) heretofore reported. These results are discussed in terms of the mechanism generating large deletions in mammalian cells and three models for the regulation of gamma-globin and beta-globin gene expression in humans.

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