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S el-Kalla

Publications and source records attributed to S el-Kalla.

8 recordsLinked to original sources
PubMed1997

A significant beta-thalassemia heterogeneity in the United Arab Emirates.

The Dubai Thalassemia Center has identified 35 different beta-thalassemia mutations in 570 chromosomes from the United Arab Emirates population using gene amplification, hybridization with specific labeled oligonucleotide probes, sequencing of amplified DNA, restriction enzymes, and amplification refractory mutation system techniques. This large number of mutations which represent 21% of the total beta-mutations discovered worldwide reflects the heterogenous nature of the population living in the United Arab Emirates (1). We found that 50% of our beta-thalassemia patients have a concomitant alpha-thalassemia; namely the -alpha 3.7 kb deletion. Co-inheritance of alpha-thalassemia especially in the form of two alpha-globin gene deletions have an ameliorating effect on the phenotype presentation of our beta-thalassemia. Nine patients (one homozygote and eight compound heterozygotes) were identified with Hb Monroe (IVS-I,-1 (G-->C)), a thalassemic hemoglobin characterized by an Arg-->Thr substitution in codon 30 of the beta-globin gene. In addition, one of the patients was a compound heterozygote for Hb Tacoma [IVS-I, +1 (G-->C)]; a point mutation affecting the third nucleotide of codon 30 (G-->C) causing an Arg-->Ser replacement.

Adolescent↗
PubMed1995

Analysis of beta-thalassemia mutations in the United Arab Emirates provides evidence for recurrent origin of the IVSI nt 5 (G-C) mutation.

Beta-thalassemia mutations were characterized in a sample of 70 patients from United Arab Emirates (U.A.E.), resulting in an enlargement of the spectrum of types found in the country. The complete association between the most common IVS I nt 5 (G-C) mutation and a specific haplotype reveals an independent origin of this mutation in U.A.E.

DNA Mutational Analysis↗
PubMed1993

Molecular characterization of beta-thalassemia in the United Arab Emirates.

This study is to identify the various beta-thalassemic alleles in the United Arab Emirates (UAE), and compare them with the UAE residents from neighboring countries suffering from the same problem. Gene amplification, dot-blot hybridization with synthetic probes, restriction enzyme analyses, and sequencing were the tools used. Thirteen different mutations were observed in the UAE patients and seventeen mutations in the non-locals. The IVS-I-5 (G-->C) Asian Indian mutation was the most frequent mutation in both groups. Homozygous mutations in both groups were relatively higher than double heterozygous mutations.

Adolescent↗
PubMedDate not supplied

A novel frameshift mutation causing beta-thalassemia in a Sikh.

During our survey of beta-thalassemia mutations among residents of the United Arab Emirates, we came across a Sikh family who had two new beta-thalassemia mutations. The father had a frameshift mutation at codons 47/48 (+ATCT), and the mother another frameshift mutation at codons 57/58 (+C). The offspring of this family were two daughters with beta-thalassemia trait and a boy with a compound heterozygosity. The boy, who was transfusion-dependent from the age of 7 months, had a successful bone marrow transplant from his eldest sister at the age of 13 months.

Base Sequence↗
PubMedDate not supplied

Genotype-phenotype correlation of sickle cell disease in the United Arab Emirates.

We have identified the beta s-globin gene haplotypes of 85 patients with sickle cell disease attending the Dubai Thalassemia Center and assessed the influence of haplotype, alpha-thalassemia, and fetal hemoglobin on the clinical presentation. Identification of the beta s haplotypes was based on mutation analyses in the promoter sequences of the G gamma- and A gamma-globin genes. The Arabian-Indian haplotype was found in 52% of the beta s chromosomes, whereas the remaining were the Bantu and Benin haplotypes. Those with the Arabian-Indian haplotype in this group had a significantly higher fetal hemoglobin (Hb F) level (mean 27%) and a milder clinical course. In contrast, those with the African haplotypes, Bantu and Benin, expressed relatively lower Hb F levels (mean 11.3%), with a severe clinical presentation. Coinheritance of alpha-thalassemia trait in the African haplotypes had an ameliorating effect on hemolytic episodes, but vaso-occlusive crises were more frequent.

Anemia, Sickle Cell↗