Epidemiological and molecular analysis of thalassemia (Beta Globin Gene) in the heterogeneous population of gwadar, Pakistan

Abstract

Abstract Heterogeneous Population of Gwadar, Pakistan Introduction and objective: Beta-thalassemia remains one of the most serious hereditary blood disorders in Pakistan, and its prevalence is rising in underprivileged regions such as Gwadar district in Baluchistan, Pakistan, primarily due to consanguineous and close-relative marriages. This study aimed to investigate the clinical, epidemiological, and molecular characteristics of thalassemia in the Gwadar District. Subjects and methods: Data was collected from 278 registered Thalassemia patients at the Hope Foundation and Thalassemia Care Center, district headquarters (DHQ) hospital Gwadar. Variables included clinical details, consanguinity, frequency of blood transfusions, and associated complications. Genetic analysis was performed on 48 blood samples. DNA was extracted, and PCR was conducted to identify mutation variants. Beta-globin gene sequencing was carried out using Sanger sequencing, and the results were analyzed using Sequencer and SnapGene (SnackVar) tools. Results: Clinical assessments revealed significant hormonal abnormalities, including delayed puberty and irregular menstrual cycles in female patients, often linked to iron overload. Twenty patients tested positive for Hepatitis C, and n=7 for HIV. The most prevalent mutation identified was IVS-I-5 (G>C), followed by the pathogenic c.47G>A (Trp16*) mutation, and a rare deletion involving amino acids 25–26, which is associated with transfusion dependency. Due to frequent blood transfusions, many patients exhibited masked microcytosis, with normal MCV levels despite parental carrier status. There were 50 recorded deaths (18% mortality) and physicians attributed the primary causes of death as severe diarrhea in HIV-positive patients and heart failure. Conclusion: Transfusion-transmitted infections are very common in this area, leading to main causes of mortality along with iron overload. The most frequent mutation identified was IVS-I-5 (G>C). The findings highlight the critical need for routine molecular diagnostics, accessible genetic screening programs, strengthened infection control measures, and comprehensive long-term care strategies tailored to the unique challenges faced by families affected by thalassemia in the Gwadar region.