Feasibility of preconception screening for thalassaemia in Indonesia: exploring the opinion of Javanese mothers.

BACKGROUND: Thalassaemia has become a major public health issue in Indonesia. It has been estimated that up to 10% of the population carries a gene associated with beta-thalassaemia. Currently, there is no formal recommendation for thalassaemia screening. This study aimed to explore awareness of thalassaemia, and to explore attitudes regarding carrier testing among Javanese mothers. METHODS: A quantitative questionnaire, designed using constructs of the Theory of Planned Behaviour, was applied cross-sectionally. RESULTS: Out of 191 mothers who were invited, 180 agreed to participate (RR = 94%), of whom 74 had a child affected with thalassaemia. Both attitudes towards receiving information about thalassaemia, and attitudes towards carrier testing were very positive. Awareness of thalassaemia was poor. Mothers, both those with and without an affected child, had barely heard of thalassaemia, nor of carrier testing. However, all mothers, including those with an affected child expressed high levels of interest in carrier testing. Respondents did not perceive that they had any control over carrier testing, and feared stigmatization and being discriminated against if their carrier status was identified. Attitudes towards carrier testing explained 23% of future reproductive intentions, in addition to perceived stigmatization, education level and 'mother's age' (R (2)=0.44; p=0.001). CONCLUSION: Responding mothers expressed high levels of interest in receiving information on both thalassaemia and carrier testing. The less educated and the more deprived they were, the keener they were to receive this information. Overall, awareness of thalassaemia was low. Even mothers with affected children seemed unaware of the inheritance pattern and the recurrent risk of having an affected child in a subsequent pregnancy, showing the need for genetic counselling in Indonesia. It is therefore recommended not only to raise awareness about thalassaemia, but to improve the education of healthcare professionals as well.

Glucose-6-phosphate dehydrogenase deficiency and Southeast Asian ovalocytosis in asymptomatic Plasmodium carriers in Sumba island, Indonesia.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and Southeast Asian ovalocytosis (SAO) caused by a 27-bp deletion in the band 3 gene (Band3Delta 27) are well-documented genetic traits resistant to malarial diseases; however, relationships between these traits and asymptomatic malaria infection hitherto had not been investigated. Filter-blotted blood samples were collected from a total of 210 healthy individuals, 100 males and 110 females, aged 6-17 years, in Sumba island, Indonesia, to survey for the presence of Plasmodium parasites, G6PD activity and the Band3Delta 27 mutation. Presence of P. falciparum and/or P. vivax was identified in 25 subjects (11.9%). In all, 24 subjects (11.4%) showed Band3Delta 27 heterozygously. In males and females, eight and nine subjects, respectively, showed G6PD deficiency. There was no significant difference in the prevalence of asymptomatic malaria infection between individuals with or without these traits (P>0.05). No alterations in the prevalence of asymptomatic malaria infection suggest that parasite invasion into erythrocytes is unlikely to be a target phase in which the two polymorphisms demonstrate possible protective effects against malaria.

Distribution of a 27-bp deletion in the band 3 gene in South Pacific islanders.

Distribution of a 27-bp deletion in the band 3 gene (B3Delta27) that causes Southeast Asian/Melanesian ovalocytosis has scarcely been studied in remote insular Southeast Asia and New Guinea. Here the presence of the B3Delta27 was surveyed among a total of 756 subjects from the indigenous populations inhabiting New Guinean islands and remote insular Southeast Asia by using a polymerase chain reaction method. In remote insular Southeast Asia where Austronesian-speaking peoples inhabit, the B3Delta27 frequency ranged between 0.04 and 0.15. In New Guinea Island, hinterland or Papuan groups showed the absence of the B3Delta27 or a very low gene frequency (0.01 in the Gidra) of the B3Delta27. However, groups of the coastal regions (Asmat, Sorong, and others) and of the nearby islands (Biak and Manus) where Austronesian infiltration had occurred showed substantial frequencies of the deletion (0.02-0.09). It is likely that the B3Delta27 was introduced into this region about 3,500 years ago with the arrival of Austronesian-speaking peoples. Once being introduced, the B3Delta27 may have been selected because of its resistance against malaria, while founder effect and genetic drift might have occurred in the New Guinean tribes with small population size, which helped to generate a variety of the B3Delta27 frequencies.

Leber's hereditary optic neuropathy with 14484 mutation in Central Java, Indonesia.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited late-onset form of blindness characterized by acute or subacute bilateral retinal degradation resulting in a permanent loss of central vision. G11778A, C3460A, and T14484C mutations on mitochondrial DNA (mtDNA) are specific for LHON and account for most, but not all, worldwide LHON cases. A six-generation Indonesian LHON family with the T14484C mutation was analyzed. Polymerase chain reaction/restriction fragment length polymorphism analysis showed that all of the maternal lineages had the T14484C mutation in a homoplasmic form. Penetrance of the disease (33.3%) and male predominance (3:1) was similar to other worldwide LHON with the T14484C mutation. The incidence of offspring born to affected mothers was no different from that of unaffected mothers, and the age distribution of cases was no higher than that of asymptomatic carriers. Eight secondary mutations were sought but not detected. The patients of this family belonged to haplogroup M. These findings support the idea that the mtDNA backgrounds involved in the expression of LHON mutations in southeast Asians are different from those of Europeans.