Prevalence of Haemoglobin Constant Spring in the Malaysian population: Insights from a single-center study

Thalassemia is a significant public health concern in Malaysia, with an estimated 6.8% of the population being carriers. These individuals may experience varying severities of anaemia. Alpha thalassemia, in particular, results from deletions or mutations within the α- globin gene complex, leading to reduced or absent α-globin chain production. Haemoglobin Constant Spring (Hb CS) is one of the most common non-deletional alpha-thalassemia variants, characterized by a specific mutation in the HBA2 gene.

A cross-sectional study utilized data from 159 samples collected during the National Thalassemia Screening Program for Form 4 students in Terengganu from 2019 till 2022. Haemoglobin analysis was conducted with the capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) methods. DNA analysis was performed using multiplex PCR and ARMS to detect both deletional and non-deletional α-thalassemia.

Three different types of Hb CS were observed. Among the 159 samples, 137 (86.2%) were heterozygous, 20 (12.6%) were compound heterozygous, and 2 (1.3%) were homozygous for Hb CS.

These findings offer valuable insights for improving genetic counselling practices and public health strategies, especially in regions with a high prevalence of thalassemia.