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The clinical characteristics of 357 patients with hemoglobin H (HbH) disease from the Guangxi province of Southern China were studied. One hundred and ninety-one (53.3%) patients were diagnosed with HbH-Constant Spring, 19 were diagnosed with HbH Westmead. Ten patients were shown to have coinherited HbH-Constant Spring/QS with a β-thalassemia mutation. Coinheritance of the β-thalassemia gene does not alleviate anemia (8.2 ± 2.3 vs. 7.6 ± 1.7 g/dl, p = 0.276), or influence age at diagnosis (20.2 ± 19.6 vs. 12.9 ± 11.0 years, p = 0.276). Ferritin levels were significantly higher in the group of patients with the nondeletional form of the disease (475 ± 719 vs. 249 ± 264 ng/ml, p = 0.005)., (Copyright © 2010 S. Karger AG, Basel.)

Background/aims: Individuals with double heterozygosity for alpha- and beta-thalassaemia and heterozygous beta-thalassaemia show a similar haematological picture. Co-inheritance of alpha- and beta-thalassaemia in both partners may result in pregnancies with either Hb Bart's hydrops foetalis or beta-thalassaemia major, or pregnancies with both disorders., Methods: The co-inheritance of alpha-thalassaemia in 322 beta-thalassaemia carriers in Malaysia was studied., Results: The frequency of alpha-thalassaemia in the beta-thalassaemia carriers was 12.7% (41/322), with a carrier frequency of 7.8% for the SEA deletion, 3.7% for the -alpha(3.7) deletion, 0.9% for Hb Constant Spring and 0.3% for the -alpha(4.2) deletion., Conclusion: Double heterozygosity for alpha- and beta-thalassaemia was confirmed in 5 out of the 41 couples and the risk of the fatal condition Hb Bart's hydrops foetalis was confirmed in two of these couples. Detection of the Southeast Asian (SEA) deletion in the Malaysian Malays in this study confirms that Hb Bart's hydrops foetalis can occur in this ethnic group. Results of this study have provided new information on the frequency and different types of alpha-thalassaemia (--(SEA), -alpha(3.7) and -alpha(4.2) deletions, Hb Constant Spring) in Malaysian beta-thalassaemia carriers., ((c) 2008 S. Karger AG, Basel)

Background: We report cascade testing of a large Pakistani family for beta-thalassemia alleles. The family was still practicing consanguineous marriages and was at risk of having more affected births., Objective: The objective of this study was to show that identification of disease carriers in families with index cases in order to create awareness about disease and provide genetic counseling would result in reduction of the frequency of beta-thalassemia in Pakistan., Methods: In this large family with an index case, 27 available living members were tested for beta-thalassemia. Carriers of the disease were detected by measuring hemoglobin indices, and amplification refractory mutation system polymerase chain reaction was used for mutation analysis. Genetic counseling was provided to members of this family., Results: There were already 3 marriages between the carrier members and 1 between a carrier and noncarrier in this large family; 12 (44.4%) members were found to carry the mutant gene, representing a very high carrier rate compared to the 5.4% carrier frequency of beta-thalassemia in the general population of Pakistan. The family was counseled for prevention of affected births. The initially reluctant family gradually became cooperative and seriously attended the genetic counseling sessions., Conclusion: Cascade testing is more practical than general population screening in a country with limited health facilities where consanguineous marriages are practiced. This report emphasizes the need of extensive testing within families with index cases to identify the carriers of beta-thalassemia in order to reduce disease occurrence through awareness and genetic counseling., ((c) 2008 S. Karger AG, Basel)

The molecular defect was defined in 38 delta beta-thalassemic chromosomes from 30 unrelated heterozygous and 4 homozygous patients of Greek origin. Restriction fragment beta-gene cluster haplotypes were studies in 23 delta beta-thalassemic chromosomes. The molecular lesion was identical in all studied cases and corresponds to the 'Sicilian' type of delta beta-thalassemia. Restriction haplotypes analysis has shown that, with one exception only, all Greek delta beta-thalassemic chromosomes bear the polymorphic sites which characterize haplotypes I or VII, the former being probable by indirect evidence. The striking similarities of the molecular lesion and the underlying haplotypes are consistent with two theories: (1) The deletion occurred once on a chromosome and spread all over Greece and the Mediterranean area thereafter; (2) the 5' subhaplotype +----favors the deletional event in the delta-beta gene area.

The Chinese G gamma+(A gamma delta beta)zero-thalassemia is caused by a deletion of more than 80 kilobases. It has a beta(+)-thalassemia phenotype and should be differentiated from other mutations causing beta-thalassemia. Using polymerase chain reaction with three oligonucleotide primers bridging the breakpoints, the deletion can be detected easily. The method is useful in the genetic counseling and prenatal diagnosis of the at-risk families.