Gene Mutation Spectrum among Alpha-Thalassaemia Patients in Northeast Peninsular Malaysia.

(1) Background: Alpha (α)-thalassaemia is a genetic disorder that affects 5% of the world population. Deletional or nondeletional mutations of one or both HBA1 and HBA2 on chromosome 16 will result in reduced production of α-globin chains, a component of haemoglobin (Hb) that is required for the formation of red blood cells (RBCs). This study aimed to determine the prevalence, haematological and molecular characterisations of α-thalassaemia. (2) Method: The parameters were based on full blood count, high-performance liquid chromatography and capillary electrophoresis. The molecular analysis involved gap-polymerase chain reaction (PCR), multiplex amplification refractory mutation system-PCR, multiplex ligation-dependent probe amplification and Sanger sequencing. (3) Results: With a total cohort of 131 patients, the prevalence of α-thalassaemia was 48.9%, leaving the remaining 51.1% with potentially undetected α gene mutations. The following genotypes were detected: -α 3.7 /αα (15.4%), -α 4.2 /αα (3.7%), -- SEA /αα (7.4%), α CS α/αα (10.3%), α Adana α/αα (0.7%), α Quong Szeα /αα (1.5%), -α 3.7 /-α 3.7 (0.7%), α CS α/α CS α (0.7%), -α 4.2 /α CS α (0.7%), - SEA /α CS α (1.5%), - SEA /α Quong Sze α (0.7%), -α 3.7 /α Adana α (0.7%), -- SEA /-α 3.7 (2.2%) and α CS α/α Adana α (0.7%). Indicators such as Hb ( p = 0.022), mean corpuscular volume ( p = 0.009), mean corpuscular haemoglobin ( p = 0.017), RBC ( p = 0.038) and haematocrit ( p = 0.058) showed significant changes among patients with deletional mutations, but not between patients with nondeletional mutations. (4) Conclusions: A wide range of haematological parameters was observed among patients, including those with the same genotype. Thus, a combination of molecular technologies and haematological parameters is necessary for the accurate detection of α-globin chain mutations.