Abstract |
The nucleotide (nt) variations in the promoter region of the gamma-globin genes, HS-111 and 3'HS1 regions, were studied in Iranian patients with beta-thalassemia intermedia (beta-TI), beta-thalassemia major (beta-TM) and healthy individuals. Of the five nt variations at the 5' end of the ( A)gamma-globin gene, -369 (C>G), -611 (-T) and -603/604 (GA>AG) were found in all samples, whereas -588 (A>G) and -AAGC at -222 to -225 were found at different frequencies in the studied groups. Therefore, the -369, -611 and -603/604 variations were considered common mutations in this population, and the difference with respect to the -AAGC deletion was not significant. However, the A allele of the -588 variation and [+] allele of the XmnI polymorphism were more frequent in beta-TI patients, especially those who had the IVS-II-1(G>A)/IVS-II-1(G>A) genotype. The + allele of XmnI also had complete correlation with the A allele of -588 variation. The HS-111 (-21 A) variation also showed association with beta-TI patients who had high levels of Hb F. Bearing in mind that the -588 variation lies within the postulated adult-specific silencer region and that the majority of beta-TI patients had allele A, then it can be envisaged that this allele could have a role in altering the repressor function at this region. Therefore, the A allele of -588, [+] allele of XmnI and HS-111 (-21 A) variation are useful genetic markers to differentiate between beta-TM and beta-TI patients. However, these nt changes alone may not be the only elements raising the level of Hb F, other regulatory and modifying factors also play a role in Hb F production.
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Authors | Mohammad Hamid, Frouzandeh Mahjoubi, Mohammad T Akbari, Aida Arab, Sirous Zeinali, Morteza Karimipoor |
Journal | Hemoglobin
(Hemoglobin)
Vol. 33
Issue 6
Pg. 428-38
( 2009)
ISSN: 1532-432X [Electronic] England |
PMID | 19958188
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Genetic Markers
- gamma-Globins
- Fetal Hemoglobin
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Topics |
- Case-Control Studies
- Fetal Hemoglobin
(analysis)
- Gene Frequency
- Genetic Markers
- Humans
- Iran
- Polymorphism, Single Nucleotide
- Promoter Regions, Genetic
(genetics)
- beta-Thalassemia
(diagnosis, genetics)
- gamma-Globins
(genetics)
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