Page 78 - IJPS-8-2

International Journal of
Population Studies β-thalassemia mutations in Himalayan population

et al., 2017). Thalassemia is a group of inherited blood subcontinent have been widely studied (Grow et al., 2014),
disorder transferred from parents to their offspring in by various researchers in Pakistan (Usman et al., 2009),
an autosomal recessive manner. It is characterized by the Sindh (Jawahirani et al., 2007), Punjab (Garewal & Das,
abnormal production of hemoglobin. There are two forms 2003), Gujarat (Bhukhanvala et al., 2013), Tamil Nadu
of thalassemia: Alpha and beta. The beta-thalassemia (Colah et al., 2009), Maharashtra (Ambekar et al., 2001),
(β-thalassemia) is characterized by the mutations in the and Kerala (Edison et al., 2008). However, baseline data on
beta-globin gene, which leads to reduced synthesis or thalassemia were completely unavailable in the populations
absence of beta-globin chain and is responsible for causing of Garhwal region. Since the Garhwal Himalayan region
β-thalassemia disorder in individuals from different is still unexplored due to the unpredictable climatic and
ethnic groups. The DNA polymorphism in the β-globin weather conditions, the remoteness and location of
gene shows a considerable amount of variability and the place make the research unfeasible in such an area.
form a series of patterns (i.e., haplotypes), which occur at Individuals are limited to their daily needs and there is a
varying frequencies among Asian Indians (Kazazian et al., lack of knowledge and education among the public in the
1984). For the 1 time, the common seven mutations and Himalayan region. Therefore, considering the severity and
st
their haplotypes in the Indians – Frameshift β 8-9 (+G), the importance of the disorder in affecting people’s health
Nonsense Codon 15 (TGG-TAG), Frameshift β 41-42 and well-being, there is a great need to carry out such
(-TCTT), Frameshift β 16 (-C), IVS-1-5 (G-C), 619 bp studies in the population of this area.
deletion, and 13 and 25 nucleotide deletion, at 3’ end of
the gene were reported by Kazazian et al. team in the year 2. Materials and methods
1984. According to them, deletion of 619 bp was found The present research was carried out on 4,081 (2,956
to be a common mutation in the Asian Indians. Recent females and 1,125 males) unrelated individuals, from June
studies reveal that each year between 300,000 and 400,000 2016 until August 2019. The participants constituting
babies is born with serious hemoglobin disorder in low- or the study were 0 – 60 years of age and had no chronic
middle-income countries, out of which 23,000 account illness or history of infection. The ethical clearance for the
alone for β-thalassemia major with about 90% of these present research was obtained by the Institutional Ethical
births (De Sanctis et al., 2017). Committee (I.E.C.) of H.N.B. Garhwal University before
The carrier frequencies of β-thalassemia vary in the commencement of the study.
different parts of the world from 1 to 20% or they may Demographic information such as age, sex, marital
be even higher in some cases (Black et al., 2010). In status, occupation, prior history of infection, or chronic
India alone, the numbers of β-thalassemia patients are illness or surgery were obtained directly through face-to-
approximately 30 million. About 10% of the total world face interview. Only after a written consent was obtained
thalassemic individuals are born in India every year from the individuals, further study was carried out on the
(Bashyam et al., 2004). Certain communities in India, such willingly participating ones.
as Sindhis (Colah et al., 2010), Guajarati’s (Bhukhanvala
et al., 2013), Punjabis (Grow et al., 2014), and Bengalis (De Blood samples (whole blood) for the present study
et al., 1997), are commonly affected with β-thalassemia was collected from the district hospitals, public health
and the incidence varies from 1% to 17% (Gupta et al., centers, villages, schools, and local people residing in the
2003). As far as in studies conducted in different parts five major districts of Garhwal region, including Chamoli,
of the world, more than 150 – 200 mutations causing Pauri, Rudraprayag, Tehri, and Uttarkashi. A total of 5 ml
β-thalassemia have been reported (Cao & Galanello, of blood were collected from each sampled individual. The
2010). While studies conducted in India have identified blood samples were collected in Vacutainer containing
about 28 mutations in Indian populations (Old et al., ethylenediaminetetraacetic acid as anticoagulant.
2001), out of these 28 mutations, five to six mutations Twenty microliters of anticoagulated blood were utilized
are found to be common. These include IVS 1-5 (G-C), for hemoglobin analysis. NESTROFT test (Naked Eye
619 bp deletion, IVS 1-1 (G-T), Frameshift 8/9, 41/42, Single Tube Red Cell Osmotic Fragility Test) was done
and Codon 15 (Bandyopadhyay et al., 2004). The type of using 10 μl of blood, following the protocol described
mutation varies across different ethnic groups (Bashyam by Thomas et al. (1996). Approximately 2 ml blood was
et al., 2004). The frequency of mutations in carriers varies utilized for HbA analysis using high-performance liquid
2
from region to region with the predominant mutation chromatography – HPLC (Variant BioRad 2).
being IVS 1-5 (G-C) (Agarwal et al., 2000), which Out of total 4,081 blood samples analyzed for
reflects the ethnic and genetic diversity of populations. hemoglobin and NESTROFT, only 648 individuals were
The heterogeneous populations belonging to the Indian found NESTROFT positive. Further screening for HbA
2

Volume 8 Issue 2 (2022) 72 https://doi.org/10.36922/ijps.v8i2.324