Spectrum of β-Thalassemia and Other Hemoglobinopathies in the Saurashtra Region of Gujarat, India: Analysis of a Large Population Screening Program

Abstract

Hemoglobinopathies are common genetic disorders of the hemoglobin (Hb) molecule. Globally, 7.0% of the population are carriers of thalassemia with 300,000-400,000 affected births each year. There are >40 million carriers of β-thalassemia (β-thal) in India with 10,000-12,000 affected births every year. This makes control programs crucial in this vast and diverse country. The present study was undertaken to find out the burden of hemoglobinopathies, and in particular, the prevalence of β-thal carriers in the population of Saurashtra region of Gujarat in Western India. A total of 16,780 individuals, including school and college students, were screened. Complete blood counts (CBCs) and high performance liquid chromatography (HPLC) analysis were performed. We detected 1891 (11.26%) individuals with different hemoglobinopathies, of whom 758 (4.52%) were diagnosed to carry β-thal trait, 104 (0.62%) carried Hb D-Punjab (HBB: c.364G>C) trait, 61 (0.36%) carried sickle cell trait, 32 (0.19%) carried δβ-thal trait/HPFH (hereditary persistence of fetal Hb) trait, and other hemoglobinopathies were identified in smaller numbers (0.15%). We encountered 27 individuals with mean corpuscular Hb (MCH) <27.0 pg and mean corpuscular volume (MCV) <80.0 fL levels, who had borderline Hb A₂ levels (3.2-3.5%). Twenty castes showed the presence of β-thal or other hemoglobinopathies. A high prevalence of β-thal was found in the Sindhis (11.67%), Lohanas (9.71%), Brahmins (6.31%), Bharvads (6.94%), Harijans (7.57%) and Vankars (7.77%). All the heterozygotes were given appropriate counseling. A multi pronged approach, including screening of high school and college students, needs to be considered for this vast and ethnically diverse country to reduce the burden of hemoglobinopathies.

Keywords: Awareness; hemoglobinopathies; mass screening; β-thalassemia (β-thal) trait.