The genetic profile of B-cell acute lymphoblastic leukaemia diagnosed in Pretoria, South Africa: A 10-year retrospective study.
- 1Department of Haematology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
- 2Department of Haematology, Tshwane Academic Division, National Health Laboratory Services, Pretoria, South Africa.
Abstract
Background
B-cell acute lymphoblastic leukaemia (B-ALL) comprises genetically distinct subtypes with important prognostic implications. South African data suggest a different genetic landscape to other geographic regions, with a higher frequency of t(1;19). This study aimed to describe the genetic profile of B-ALL diagnosed at a South African tertiary haematology laboratory over a 10-year period.Methods
In this retrospective, descriptive study, all B-ALL cases (2014-2023) recorded in flow cytometry and cancer registries were identified. Demographic and laboratory data, including immunophenotypic and genetic findings, were extracted from the laboratory information system. Genetic work-up included karyotyping, a routine fluorescence in situ hybridisation panel: KMT2A rearrangement, t(1;19), t(12;21) and t(9;22), and real-time quantitative polymerase chain reaction where available.Results
A total of 173 patients were included (54.9% male; 75.7% < 19 years). Genetic testing was requested in 146 cases (84.4%), with definitive results in 115 (78.8%). Among informative cases, t(1;19) was most frequent (26.1%), followed by t(9;22) (12.2%), t(12;21) (10.4%), high hyperdiploidy (9.6%), KMT2A rearrangement (7.0%) and hypodiploidy (0.9%). The t(1;19) translocation predominated in paediatric patients, while t(9;22) was more common in adults. Both t(12;21) and KMT2A rearrangements were restricted to patients < 19 years.Conclusion
This cohort demonstrates a high frequency of t(1;19) and age-specific variation in B-ALL genetic subtypes, suggesting a distinct regional genetic profile. Expanded diagnostic testing and multicentre African studies are needed to refine risk stratification and guide context-appropriate care.Contribution
This study provides data on the distribution of selected genetic subtypes of B-ALL in a South African population, identifying differences in subtype frequency and age distribution that may inform regional diagnostic strategies and risk-directed care.
Related
- Reduced‐dose versus standard‐dose total body irradiation before allogeneic haematopoietic stem cell transplantation in adults with acute lymphoblastic leukaemia
- Case Report: Diagnostic and management challenges of necrotizing fasciitis in an immunocompromised child with acute lymphoblastic leukaemia
- Locally manufactured point-of-care CD19 chimeric antigen receptor T-cell therapy for paediatric relapsed/refractory B-cell acute lymphoblastic leukaemia: a single-centre feasibility experience
- A Case of Autosomal Dominant Alport Syndrome with Normal Type IV Collagen α5 Staining Diagnosed by a Genetic Analysis
- Incidence of diabetes remission and association with microvascular and macrovascular complications in patients with newly diagnosed type 2 diabetes mellitus: a retrospective cohort study using real-world data in Thailand.
BibTeX
@article{olivier2026genetic,
title = {{The genetic profile of B-cell acute lymphoblastic leukaemia diagnosed in Pretoria, South Africa: A 10-year retrospective study.}},
author = {Kirsten Olivier and Annelli Marais and Keryn Thompson and Amery Badenhorst and Angela Tennant and Joachim Potgieter},
journal = {Journal of the colleges of medicine of South Africa},
year = {2026},
month = oct,
doi = {10.4102/jcmsa.v4i1.432},
url = {https://europepmc.org/article/MED/43011188},
note = {CC BY},
}
RIS
TY - JOUR
TI - The genetic profile of B-cell acute lymphoblastic leukaemia diagnosed in Pretoria, South Africa: A 10-year retrospective study.
AU - Kirsten Olivier
AU - Annelli Marais
AU - Keryn Thompson
AU - Amery Badenhorst
AU - Angela Tennant
AU - Joachim Potgieter
PY - 2026
DA - 2026/10/13
JO - Journal of the colleges of medicine of South Africa
DO - 10.4102/jcmsa.v4i1.432
UR - https://europepmc.org/article/MED/43011188
AB - Background B-cell acute lymphoblastic leukaemia (B-ALL) comprises genetically distinct subtypes with important prognostic implications. South African data suggest a different genetic landscape to other geographic regions, with a higher frequency of t(1;19). This study aimed to describe the genetic profile of B-ALL diagnosed at a South African tertiary haematology laboratory over a 10-year period.Methods In this retrospective, descriptive study, all B-ALL cases (2014-2023) recorded in flow cytometry and cancer registries were identified. Demographic and laboratory data, including immunophenotypic and genetic findings, were extracted from the laboratory information system. Genetic work-up included karyotyping, a routine fluorescence in situ hybridisation panel: KMT2A rearrangement, t(1;19), t(12;21) and t(9;22), and real-time quantitative polymerase chain reaction where available.Results A total of 173 patients were included (54.9% male; 75.7% < 19 years). Genetic testing was requested in 146 cases (84.4%), with definitive results in 115 (78.8%). Among informative cases, t(1;19) was most frequent (26.1%), followed by t(9;22) (12.2%), t(12;21) (10.4%), high hyperdiploidy (9.6%), KMT2A rearrangement (7.0%) and hypodiploidy (0.9%). The t(1;19) translocation predominated in paediatric patients, while t(9;22) was more common in adults. Both t(12;21) and KMT2A rearrangements were restricted to patients < 19 years.Conclusion This cohort demonstrates a high frequency of t(1;19) and age-specific variation in B-ALL genetic subtypes, suggesting a distinct regional genetic profile. Expanded diagnostic testing and multicentre African studies are needed to refine risk stratification and guide context-appropriate care.Contribution This study provides data on the distribution of selected genetic subtypes of B-ALL in a South African population, identifying differences in subtype frequency and age distribution that may inform regional diagnostic strategies and risk-directed care.
SN - 2960-110X
ER -