Molecular basis of beta thalassaemia intermedia in Pakistan.

Objective: To investigate the primary β-globin gene mutations and their association with secondary genetic modifiers—Xmn-1 polymorphism and BCL11A variant—in patients diagnosed with β-thalassemia intermedia in Pakistan. Study Design: Descriptive Cross-sectional study. Setting: Fauji Foundation Hospital, Islamabad. Period: June 2021 to January 2022. Methods: Seventy patients with β-TI were enrolled. DNA was extracted using the Chelex method, and molecular analysis was performed using PCR-RFLP and ARMS-PCR to detect BCL11A (rs11886868) and Xmn-1 polymorphisms, respectively. Statistical analysis was carried out using SPSS version 17. Results: The most frequent primary mutations included Cd-15 (14.3%), IVSI-5 (11.4%), and Fr 8-9 (12.9%). Xmn-1 and BCL11A polymorphisms were identified in 37.1% and 71.4% of patients, respectively. Statistically significant associations were found between certain primary mutations (e.g., IVSI-5 and IVSI-5/cap +1) and both secondary modifiers (p < 0.001 and p = 0.005, respectively). Dual modifier presence was observed in 26% of patients. Conclusion: This study reveals considerable molecular diversity in β-thalassemia intermedia in Pakistan. The significant association between specific β-globin mutations and secondary genetic modifiers highlights the complex genotype-phenotype interplay. These findings underscore the need for larger, multi-centric genetic studies to enhance predictive accuracy for clinical management and personalized therapy in thalassemia.