Is thalassemia common in individuals of Malay ethnicity?

Thalassaemia Prevalence in the Malay Ethnic Group

Thalassaemia is highly prevalent in the Malay ethnic group, with approximately 4.5-5.0% of Malaysians being carriers of this genetic disorder, and Malays comprising the largest affected ethnic group at 63.95% of all thalassaemia patients in Malaysia. 1, 2

Epidemiology of Thalassaemia in Malaysia

• According to the Malaysian Thalassaemia Registry, Malays represent the predominant ethnic group affected by thalassaemia (63.95%), followed by Chinese (13%) and Kadazan-Dusun (13%) 1, 2
• As of 2018,7,984 patients with thalassaemia were reported alive in Malaysia 1
• The state of Sabah has the highest concentration of thalassaemia cases (22.72%) 1
• The majority of affected individuals are between 5.0-24.9 years old (64.45%) 1

Types of Thalassaemia in Malays

Beta-Thalassaemia

• The most common β-thalassaemia mutations in the Malay ethnic group include:
  • Codon 19 (A>G) (Hb Malay)
  • IVS-I-1 (G>T)
  • IVS-I-5 (G>C)
  • Polyadenylated signal (polyA) (AATAAA>AATAGA) 2
• Haemoglobin E (Hb E) is particularly significant, accounting for 76% of β-thalassaemia mutations in Malays 2
• Hb E/β-thalassaemia is the most common diagnosis (34.37%) among Malaysian thalassaemia patients 1

Alpha-Thalassaemia

• Alpha-thalassaemia is also prevalent in the Malay population, with eight common deletions and mutations identified, including:
  • Three double gene deletions
  • Two single gene deletions
  • Three nondeletional mutations 2

Clinical Impact and Management

• 56.73% of thalassaemia patients in Malaysia require regular blood transfusions 1
• 61.72% are on chelation therapy 1
• 14.23% have undergone splenectomy 1
• Cardiac complications remain the main cause of death despite improvements in iron overload management 1

Public Health Response

• The Malaysian National Programme for Thalassaemia Prevention and Control was launched in 2004 2
• The program includes:
  • Mass public education campaigns
  • Population screening
  • Laboratory diagnosis
  • Comprehensive patient management
  • Malaysian Thalassaemia Registry 2

Screening and Prevention Challenges

• Despite the high prevalence, public awareness remains an issue, with a study showing that while 76.4% of Malaysians have heard of thalassaemia, knowledge scores remain moderate 3
• Only 13.6% of married participants reported being screened for thalassaemia 3
• Cultural factors influence attitudes toward prevention strategies, with 63.4% being unsupportive of selective termination of fetuses diagnosed with thalassaemia major 3

Clinical Implications

• Carrier and premarital screening programs may be more effective and culturally acceptable approaches for prevention 3
• Alpha-thalassaemia can lead to severe conditions like Hb Bart's hydrops fetalis, which is associated with fetal death 4
• In regions with high prevalence of alpha-thalassaemia (like Southeast Asia), it accounts for 28-55% of non-immune hydrops fetalis cases 4
• Parents can be screened by evaluation of mean cell volume, which will be <80 fL in thalassaemia carriers 4

Thalassaemia represents a significant public health challenge in Malaysia, particularly among the Malay ethnic group. The high prevalence underscores the importance of continued screening, genetic counseling, and public education efforts to reduce the disease burden and improve outcomes for affected individuals.