Publication:

Molecular screening of β-thalassemia mutations among anaemic children and the influence of consanguinity: a hospital-based cross sectional study from South India

Background β-thalassemia is the most common inherited haemoglobin in India, affecting 3-4% of the population. Mutations in the β-globin gene cause defective haemoglobin synthesis and chronic anaemia. Consanguineous marriage increases the risk of homozygosity for autosomal recessive disorders. Early molecular diagnosis is essential for differentiating inherited haemoglobinopathies from nutritional anaemia and for implementing preventive strategies. This study aimed to detect β-thalassemia mutations among anaemic children and evaluate the association between parental consanguinity and mutation positivity.

Methods A hospital-based cross-sectional study was conducted between September 2021 and October 2022 among 40 children with severe anaemia, haemoglobin <8 g/dL. Demographic and clinical information, including parental consanguinity, was collected. Molecular screening for β-thalassemia mutations was performed using Real-Time PCR  with the SNP Biotech Beta Thalassemia Kit on the 7500 AB systems. Statistical analyses included Chi-square test, odds ratio (OR), relative risk (RR), and 95% confidence intervals (CI).

Results Of 40 children, 13 (32.5%) tested positive for β-thalassemia mutations. Mutation positivity was 33.3% among consanguineous families and 31.2% among non-consanguineous families. Statistical analysis showed no significant association between consanguinity and mutation positivity (χ²=0.019, p=0.890). Odds ratio analysis indicated slightly higher odds among consanguineous families (OR=1.10; 95% CI: 0.28-4.27).

Conclusions β-thalassemia mutations were identified in a substantial proportion of severely anaemic children. Although prevalence was marginally higher in consanguineous families, comparable rates in non-consanguineous families highlight the widespread carrier burden. Molecular screening is valuable for early diagnosis, family screening, genetic counselling, and prevention of severe β-thalassemia.