Hemoglobin S (HbS, α2β26GluVal) merupakan variasi hemoglobin yang terbentuk hasil daripada mutasi GAG GTG pada kodon 6 gen β-globin. Hemoglobinopati haemoglobin S (HbS) jarang ditemui di kalangan penduduk Malaysia tetapi selalunya dijumpai di kalangan pendatang asing dari Afrika. Walau bagaimanapun beberapa kes didapati dalam kaum India dan Melayu. Kajian ini meninjau keputusan makmal pesakit HbS dan penggunaan “multiplex ligation-dependent probe amplification” (MLPA) dan “flow-through hybridization” (FTH) dalam mengesan mutasi HbS. HbS dikenalpasti melalui kromatografi cecair prestasi tinggi (HPLC) dan/atau elektroforesis kapilari serta elektroforesis hemoglobin. Analisis molekul dijalankan menggunakan kaedah MLPA, FTH dan penjujukan Sanger. Dua warga Afrika, tiga Melayu dan dua India berusia antara 2-31 tahun telah dikenalpasti. Lima pesakit adalah HbS homozigot, seorang kompaun heterozigot HbS/β-talasemia dan seorang lagi pembawa HbS. Tahap hemoglobin (Hb) kes HbS homozigot adalah antara 7.4-10.2 g/dL dengan aras HbS dan HbF diantara 58.3-94.7% dan 1.5-35.5%. Hb untuk kes kompaun heterozigot HbS/β-talasemia adalah 5.8 g/dL dan normal pada pembawa HbS. Aras HbS, HbF dan HbA2 untuk HbS/β-talasemia dan pembawa HbS adalah 67%, 27.2% dan 4.2%, dan 38.6%, 0.1% and 2.8% setiap satu. Kedua-dua kaedah MLPA dan FTH berjaya mengesan mutasi HbS dalam semua kes, manakala cuma FTH dapat menentukan zygositi mutasi HbS dan β-talasemia dalam satu ujian yang sama.
G6PD deficiency is the commonest enzyme deficiency found in humans. Current diagnostic methods lack sensitivity to detect all cases of G6PD deficiency. We evaluated the reverse dot blot flow-through hybridisation assay designed to detect simultaneously multiple known G6PD mutations in a group of Malaysian neonates. Archival DNA samples from 141 G6PD-deficient neonates were subjected to reverse dot blot flow-through hybridisation assay using the GenoArray Diagnostic Kit (Hybribio Limited, Hong Kong) and DNA sequencing. The method involved PCR amplification of 5 G6PD exons using biotinylated primers, hybridisation of amplicons to a membrane containing oligoprobes designed for G6PD mutations known to occur in the Malaysian population and colour detection by enzyme immunoassay. The assay detected 13 of the 14 G6PD mutations and genotyped 133 (94.3%) out of 141 (102 males, 39 females) cases. Among the 39 female G6PD-deficient neonates, there were 7 homozygous and 6 compound heterozygous cases. The commonest alleles were G6PD Viangchan 871G > A (21%) and G6PD Mahidol 487G > A(20%) followed by G6PD Mediterranean 563C > T, (14%), G6PD Vanua Lava 383T > C (12%), G6PD Canton 1376G > T (10%), G6PD Orissa 131C > G (6.3%) G6PD Coimbra 592C > T (5.6%) plus 6 other mutations. DNA sequencing of remaining cases revealed 6 cases of intron 11 nt 93C > T not previously reported in Malaysia and two novel mutations, one case each of nt 1361G > T and nt 1030G > A. We found the reverse dot blot assay easy to perform, rapid, accurate and reproducible, potentially becoming an improved diagnostic test for G6PD deficiency.