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A study of beta-gene mutations in Jat Sikhs, a subcaste of Punjabis, revealed a very high prevalence (46%: 41/88) of the mild beta++ promoter region mutation -88 (C-T). Sixteen individuals presenting in homozygous form were clinically mild. Un-transfused patients had characteristic hematological findings: high Hb F (38.1-68.6%, mean 47.4%), high Hb A2 (5.7-9.8%, mean 6.88%), and the rest had adult hemoglobin. The 19 subjects with compound heterozygosity for -88 (C-T) and another beta-gene mutation presented both as thalassemia intermedia (four cases) and as thalassemia major (15 cases). One of the four patients with the milder phenotype had a second mild mutation, CAP+1 (beta++). In the other three cases with the milder phenotype, the second mutation was associated with the presence of the XmnI Ggamma polymorphism. Notably, the XmnI Ggamma was negative in all the -88 (C-T) alleles. None of the patients had associated alpha-thalassemia even in the thalassemia intermedia group. Haplotype analysis of the -88 (C-T) homozygous cases showed a single haplotype (+ - - - - + -) in all but two individuals. This haplotype is distinct from those described in the Africans with homozygous -88 (C-T), suggesting that the mutation in our population occurred independently., (Copyright (c) 2005 Wiley-Liss, Inc.)

Aplastic anemia is characterized by pancytopenia with hypoplastic bone marrow. Various factors including viral infections have been implicated as the precipitating factors. Human parvovirus B19 has been associated with red-cell aplasia, leukopenia, and thrombocytopenia. The present study was carried out to determine the role of parvovirus B19 in aplastic anemia patients. Twenty-seven aplastic anemia patients and 20 healthy controls were tested for the presence of parvovirus B19 infection by detecting parvovirus B19-specific IgM by ELISA and viral DNA by PCR. Parvovirus B19 IgM and viral DNA were detected in significantly higher numbers of patients in comparison to the controls (40.7% vs. 5%, P < 0.01; 37% vs. 0%, P < 0.001, respectively). The presence of parvovirus DNA in aplastic anemia patients indicates active or recent infection. However, more studies are needed to explore the mechanism of bone-marrow aplasia due to human parvovirus B19 infection.