https://orcid.org/0009-0000-8129-0051
Key Points
D-negative blood units and donors are rare in East and Southeast Asia.
The prevalence of Asian-type DEL among Malay D-negative individuals is higher than in most East Asian populations.
Red cell genotyping can improve the allocation of rare D-negative blood, conserve resources, and reduce unnecessary RhIG injections.
The study proposes managing patients and pregnant women with Asian-type DEL as D-positive in Malaysia, which could serve as a model for other Southeast Asian countries.
Abstract
In East and Southeast Asia, D-negative blood units and donors are rare (<0.5%). A recent prospective clinical trial suggested that patients with the Asian-type DEL (RHD*DEL1) can be safely managed as D-positive. However, despite a clinically relevant prevalence of Asian-type DEL (typically 17%) in East Asia, data on its prevalence in the Malay population were lacking. We reviewed Rh phenotyping records of blood donors in Terengganu, Malaysia, collected over 4 years, and conducted molecular analysis of the RHD gene on serologic D-negative blood donors and patient samples collected in 2024. Among 33,829 blood donors, 179 (0.53%) were serologic D-negative, with the highest prevalence (5%) in Indian donors. The prevalence of Asian-type DEL was found to be 25% among Malay D-negative blood donors and 21% among Malay patients, higher than in most East Asian populations. The findings suggest that implementing red cell genotyping can improve the precise allocation of red cell resources, conserve the supply of rare D-negative blood, and eliminate unnecessary RhIG injections.
Author notes
Conflict of interest disclosure: The authors declared having no competing financial interest.
Statement of Disclaimer: The views, information or content, and conclusions presented do not necessarily represent the official position or policy of, nor should any official endorsement be inferred on the part of, the Clinical Center, the National Institutes of Health, or the Department of Health and Human Services.
Data Sharing Statement: The data that support the findings of this study are available from the corresponding author upon reasonable request.
Authorship contribution: MMBK and WAF designed the study approach and developed the rationales. MMBK and KS designed and performed the molecular experiments, retrieved literature, and wrote a draft. MMBK and KS analyzed the molecular data with WAF. MMBK, KS and WAF discussed the data and wrote the manuscript.
Funding. This work was supported by the Intramural Research Program (project ZIC CL002128) of the NIH Clinical Center at the National Institutes of Health (WAF). The fellowship placement at NIH (KKM510-4/5/1/16715(9) & NIHCA2496840) was supported by the Ministry of Health Malaysia (MMBK).
