Hb Narges Lab, a Novel Hemoglobin Variant of the ß-Globin Gene.

In this study, we describe a new missense variant on the ß-globin gene in a heterozygous form in a female individual. Standard methods were used to determine red blood cell indices and perform hemoglobin analyses. Molecular studies were performed on the genomic DNA isolated from peripheral blood cells. Beta-globin genes were amplified and sequenced. We report a novel mutation on the ß-globin gene (HBB), c.134 C>T; p.S44F variant, in the heterozygote state which was detected in a female of Persian ethnic origin in the Khuzestan province, southern Iran, that we named Hb Narges Lab (HbNL) variant. This mutation was predicted to be disease-causing in all except one in silico prediction tools. This variant was reported for the first time worldwide, had no shown hematological abnormalities but should be considered when inherited in the compound heterozygous form with ß- thalassemia (ß0-thal) carrier, which might result in the phenotype of thalassemia intermedia.

Genotype-phenotype correlation in patients with deletional and nondeletional mutations of Hb H disease in Southwest of Iran.

We studied the alpha-globin gene genotypes, hematologic values, and transfusion-dependence of patients with Hb H disease. Molecular characterization of alpha-thalassemia was performed. We identified 120 patients with Hb H disease. Of these patients, 35 (29.16%) had deletional form of Hb H disease, and 85 (70.83%) had different form of non-deletional Hb H disease. The most frequently observed Hb H genotypes were --Med/-α3.7 in 33 patients (27.5%), αCD19(-G) α/αCD19(-G) α in 25 cases (20.83%), αpolyA2α/αpolyA2α in 15 (12.5%), and αpolyA1α/αpolyA1α in 13 (10.83%) respectively. The probability of receiving at least one transfusion blood in deletional form was observed in 3 of 35 (8.57%) patients which just seen in 3 of 33 (9%) patients with --Med/-α3.7 genotype. This form was also observed in 8 of 85 (9.4%) patients in non-deletional Hb H diseases which five of them had Med deletion in compound with alpha globin point mutations. Nondeletional Hb H disease was more severe than deletional Hb H disease requiring more blood transfusions. We can recommend that Med deletion in compound with alpha-globin point mutations, polyA1 and constant spring in homozygous form needs to be taken into consideration when offering counseling to high-risk couples.

Alpha-globin gene triplication and its effect in beta-thalassemia carrier, sickle cell trait, and healthy individual.

The genotype and phenotype correlation between coinheritance of heterozygous beta-thalassemia with the alpha-globin triplication is unclear. In this study we have investigated and reviewed alpha triplication frequency in beta-thalassemia carriers, sickle cell trait, and healthy individuals and its effect on hematological and phenotypical changes. In this study, 4005 beta-thalassemia carriers, 455 sickle cell trait, and 2000 healthy individuals were included. Molecular characterization of beta and alpha-thalassemia was performed. The frequencies of alpha-globin triplication in beta-thalassemia carriers, sickle cell trait, and healthy individuals were 67 (1.67%), 4 (0.88%), and 18 (0.9%), respectively. In total, the frequency of alpha-triplications is approximately 89 (1.39%) in Khuzestan province, South of Iran population. We have compared the average hematological parameters of beta-thalassemia carriers, sickle cell trait, and healthy individuals with and without alpha gene triplication. This mutation did not show any significant effect on the change of blood indices, neither in healthy individuals nor in sickle cell trait and beta-thalassemia carriers. Therefore, there is no need to take more notice of anti 3.7 mutation in beta-thalassemia carriers is opposed with some studies reported that the presence of excess alpha-globin genes in beta-thalassemia carriers can lead to the phenotype of beta-thalassemia intermedia. Therefore, not every individual with triplicated alpha globin coinherited with beta-thalassemia trait will have a significantly lower Hb than normal, and it is highly likely that none of them will need transfusion.

Two Novel and Five Rare Mutations in the Non Coding Regions of the ß-Globin Gene in the Iranian Population.

ß-Thalassemia (ß-thal) is one of the most frequent genetic disorder in Iran with great mutational diversity. In this study, we describe two novel and five rare mutations in the non coding regions of the ß-globin gene; these mutations were identified in the non coding regions of the ß-globin gene (HBB) in the heterozygous state. Three alterations were detected in the promoter region, including -9 (C>G) [HBB: c.59C>G (novel mutation)], -54 (G>A) (HBB: c.-104G>A) and -57 (A>T) (HBB: c.-107A>T), three changes in the 5' untranslated region (5'UTR) including +11 (C>G) [HBB: c.-40C>G (novel mutation)], +41 (A>T) (HBB: c.-10A>T) and +43 (C>G) (HBB: c.-8C>G) and one mutation in the 3'UTR 62 (A>G) (HBB: c.*62A>G). Five mutations including -54, -57, +41, +11 and +43 were predicted to be deleterious in all except one in silico prediction tool, and the remaining two mutations were found to be most likely polymorphisms. In conclusion, two novel mutations were reported for the first time worldwide and five rare changes have not been reported previously in any other part of Iran. In the absence of further data, it is not possible to consider them as mutations that determine an ascertained healthy carrier state.

The First Report of a 290-bp Deletion in ß-Globin Gene in the South of Iran.

BACKGROUND: ß-thalassemia is one of the most widespread disease in the world, including Iran. In this study, we reported, for the first time, a 290-bp ß-globin gene deletion in the south of Iran. METHODS: Four individuals from three unrelated families with Arabic ethnic background were studied in Khuzestan Province. Red blood cell indices and hemoglobin analysis were carried out according to the standard methods. Genomic DNA was obtained from peripheral blood cells by salting out procedures. ß-globin gene amplification, multiplex ligation-dependent probe amplification (MLPA) and DNA sequencing were performed. RESULTS: The PCR followed by sequencing and MLPA test of the ß-globin gene confirmed the presence of a 290-bp deletion in the heterozygous form, along with -88C>A mutation. All the individuals had elevated hemoglobin A2 and normal fetal hemoglobin levels. CONCLUSIONS: This mutation causes ß0-thalassemia and can be highly useful for prenatal diagnosis in compound heterozygous condition with different ß-globin gene mutations.

A novel alpha-thalassemia nonsense mutation in HBA2: C.382 A > T globin gene.

In this study, a new alpha globin gene mutation on the α2-globin gene is reported. This mutation resulted in a Lys > stop codon substitution at position 127 which was detected in four individuals (three males and one female). DNA sequencing revealed this mutation in unrelated persons in Khuzestan province, Southwestern Iran of Lor ethnicity. This mutation caused no severe hematological abnormalities in the carriers. From the nature of substituted residues in α2-globin, it is widely expected that this mutation leads to unstable and truncated protein and should be detected in couples at risk for α-thalassemia.

Identification of IVS-I (-1) (G > C) or Hb Monroe as a report on the beta-globin gene with a beta-thalassemia minor phenotype in south of Iran.

We described the first report of IVS-I (-1), codon 30 (G > C) or Hb Monroe in five individuals from four unrelated families in Khuzestan Province. Polymerase chain reaction (PCR) followed by sequencing of the beta-globin gene confirmed the presence of Hb Monroe in the heterozygous form which causes beta-thalassemia due to missplicing in the course of mRNA processing. This mutation has been described in individuals originated from Arabic and Behbahani origins, Ahvaz City, south of Iran. The knowledge of the beta-globin variants present in the Iranian population is essential for the molecular diagnosis and prevention of hemoglobinopathies.

Hb AHVAZ [α83(F4)Leu→Arg, CTG>CGG (α2); HBA2: c.251T>G],a new hemoglobin variant of the α2-globin gene.

We report a novel mutation on the α2-globin gene, codon 83 (T>G), which was detected in two members of two unrelated families from Khuzestan Province, South Iran, that we named Hb Ahvaz. This mutation was detected by cellulose acetate electrophoresis and characterized by molecular studies. Hb Ahvaz does not seem to be responsible for hematological abnormalities in the carriers, but with α(0)-thalassemia (α(0)-thal) defects, might induce severe clinical symptoms.