Biomedical subjects

Man Sim Wong

Publications and source records attributed to Man Sim Wong.

2 recordsLinked to original sources

PubMed2004

A thalassaemia array for Southeast Asia.

The alpha and beta thalassaemias are the commonest genetic disorders worldwide. The homozygous state is associated with high morbidity and mortality, thus screening of at-risk pregnancies and prenatal testing are strongly advocated. A thalassaemia (thal) array has been designed using allele-specific arrayed primer extension (AS-APEX) for the simultaneous analysis of 15 non-deletion alpha-gene defects and 23 beta-gene mutations commonly found in southeast Asian countries, where thalassaemias are highly prevalent. This overcomes the problem of using multiple reverse dot blot analysis. The array showed 100% sensitivity and specificity in the detection of 120 beta-thal mutants and 35 non-deletion alpha-thal mutants. It is robust enough to be produced in a single place and shipped to other laboratories for use. The production cost of the array is low, each slide can be used for three different test samples and is therefore amenable to large scale antenatal screening in southeast Asian countries.

Asia, Southeastern↗

PubMedDate not supplied

Can defects in transferrin receptor 2 and hereditary hemochromatosis genes account for iron overload in HbH disease?

Iron overload was found to be the major cause of disability in Chinese HbH disease patients although they were not on regular blood transfusion. The transferrin receptor 2 (TFR2) and hereditary hemochromatosis (HFE) genes were examined to see if inheritance of these gene defects may be a possible cause of iron overload in 45 HbH patients. A novel intronic (IVS6 (+6) T-->A) mutation of the TFR2 gene was identified in one patient, and six others were found to carry a known missense mutation (exon 5, I238M) that was also present in one normal control subject. One HbH patient and one normal control carried the H63D mutation of the HFE gene. Since only eight out of 45 iron-overloaded HbH patients carry a defect in the TFR2 or HFE gene in the heterozygote state and their iron loading status was comparable to the matched controls without such defects, it would appear that the accumulation of excess iron in HbH disease is more likely a result of increase dietary absorption secondary to ineffective erythropoiesis.

Alleles↗