Genetic Hemoglobin Disorders Among the People of Assam-A Tertiary Care Hospital Based Study

Received: 17-Dec-2022, Manuscript No. ijmrhs-23-83958; Editor assigned: 19-Dec-2022, Pre QC No. ijmrhs-23-83958 (PQ); Reviewed: 24-Dec-2022, QC No. ijmrhs-23-83958 (Q); Revised: 27-Jan-2023, Manuscript No. ijmrhs-23-83958 (R); Published: 30-Jan-2023

Introduction

Hemoglobinopathies and thalassemia are genetic hemoglobin diseases and are prevalent worldwide. Southeast Asian countries have a high prevalence of these Hb variants. The Northeast region of India is a hot spot for these hemoglobinopathies and thalassemia. The majority of variant hemoglobins differ from the normal in that a single amino acid has been substituted for another [1]. Also, double heterozygosity cases have been reported earlier like HbS-HbE but are rare. A case of Hb S-beta thalassemia was reported from Assam [2]. The most frequently encountered structurally variant hemoglobins are Hb S, Hb C, Hb D Punjab, and Hb E [3].

Thalassemia is a form of severe anemia occurring early in life and associated with splenomegaly and bone marrow changes [4]. The thalassemias are found in a broad belt extending from the Mediterranean basin to India and the orient [5]. Nearly 200 different mutations have been described in patients with β-thalassemia. Among them, about 28 mutations have been documented in Indian patients. Six mutations, 619 bp deletion at 3’ end of a β-Globin gene, IVS1-5 (G→C), IVS1-1 (G→T), frame-shift mutations codon 8/9, codon 41/42 and nonsense codon 15, account for 90%-94% of the beta-mutations in India [6].

Hemoglobin E trait is the third most common hemoglobin disorder in the world and Southeast Asia, its prevalence is estimated to be 30%. Although the Hemoglobin E trait is associated with no morbidity, the offspring of individuals who carry this hemoglobin variant may exhibit clinical manifestations like β-thalassemia major (Compound hemoglobin E- β-thalassemia) if the other parent has β-thalassemia trait and contributes that gene. This combination is the most common cause of transfusion-dependent thalassemia in areas of Southeast Asia [7].

Hemoglobin D Punjab is found with the greatest prevalence (2%) among the Sikhs of Punjab in India as well as in nearby Gujarat (1%). About 5% of the world’s population is a carrier of a potentially pathological hemoglobin gene [8]. The β-thalassemias are widespread throughout the Mediterranean region, Africa, Middle-east, the Indian subcontinent, and Burma, Southeast Asia. Estimates of gene frequencies vary from 3%-10% in some areas [9]. About 3% of the world’s population (around 150 million people) carries β-thalassemia genes [10].

The inherited disorders of the blood include hemoglobinopathies one of the major public health problems in India [11]. The cumulative gene frequency of the three most predominant variant hemoglobins i.e. Sickle cell, HbD, and HbE has been estimated to be 5.35% in India. Thus, there is a tremendous amount of burden of hemoglobinopathies in India [12].

The Bodo-Kachari has a gene frequency of 0.50 for Hb E, the highest anywhere in the world [13]. HbE mutation among the Bodo-Kachari of Assam is found to be the highest observed frequency in the world followed by the tribes of adjoining Tripura [14].

β-thalassemia is detectable in almost every Indian population; however, it is seen with the highest frequency in the northwest and far east. Sindhis, Gujaratis, Bengalis, Punjabis, and Muslims account for most of β-thalassemia. The carrier state for β-thalassemia in India varies from 1%-17% with an average of 3.2%. α-thalassemia is most widely prevalent in the tribal population with a frequency of 1%-40% in Andhra Pradesh and Gujarat. Subsequently, Hb S has been reported from various Indian states, communities, and ethnic groups with an average frequency of 4.3% (range: 0%-44%). The sickle gene in India is mostly found among Dravidian and pre-Dravidian tribes. Hb D is predominantly seen in Punjab, Uttar Pradesh, Gujarat, Jammu and Kashmir. It is most prevalent in Punjabi, Sikh, and migrant Sindhi populations [15].

The presence of HbE in all of the five examined members of an Assamese Tibeto-Burman group, the Kachari was unexpected because of the virtual absence of HbE in the Tibeto-Burmans of Tibet, Nepal [16]. Researchers in South East Asia provided further pieces of evidence of α and β thalassemia. The frequencies of HbE were determined in many groups living in the northeastern part of Thailand [17]. A subsequent larger survey in upper Assam proved the high frequency of HbE among the Kachari and documented a frequency of 0.5 [18]. Similarly, high frequencies of HbE were found in other Bodo Tibeto-Burman groups in Assam, e.g. the Bodo-Kachari of lower Assam, the Garo, the Rabha, and the Tiwa [19]. Earlier it was reported that the Hindu caste population of Assam shows the lowest prevalence of HbE, and within this group, the frequency of HbE is significantly lower in the Brahmin. The Muslim group largely of Assamese stock has a similar frequency of HbE [20]. Previously the only report on β thalassemia in Assam showed a 1.5 frequency of 5.5% among 182 Indeed Assamese, 1.5% among 129 Ahom, and 2.9% among 140 Khasis. HbE mutation among the Bodo Kachari population of Assam (North-East India) has been reported to be 64.5%, the highest observed frequency of this mutation in the world [21].

A high incidence of hemoglobinopathies and thalassemia has been detected in the Northeast region of India and their combination is unique for this part of the country [22]. In a hospital-based study, the occurrence of hemoglobinopathies and thalassemia in Northeast India was reported to be around 50% [23]. There is a high occurrence rate of hemoglobinopathies and thalassemia in Assam. Hb E is the most common Hb variant found in Assam, India followed by beta thalassemia, Compound HbE-Beta Thalassemia, and Hb S [24].

The most effective approach to reducing the burden of society is to reduce the incidence by implementing a screening program, offering genetic counseling, prenatal diagnosis, and selective termination of pregnancy of the affected fetuses in India. Health education is an important component of preventive genetic programs [25].

Studies related to these types of genetic disorders help in putting forward the real scenario of the disease which is prevalent in society and help the Government to take up and put forward new programs which may help in curbing the disease.

Methods

Ethical Clearance was taken from the Institutional Ethical Committee to carry out this hospital-based study. The necessary details of patients were filled up in a proforma and blood samples were collected in EDTA-coated vacutainers after taking written informed consent.

Blood samples were collected from the suspected Anemic patients attending the Out Patient Department of Gauhati Medical College and Hospital, a tertiary care hospital within 2 years. Patients with Anaemia were included in the study while patients who had a history of blood transfusion in the last 3 months were excluded from the study. A total of 1118 patients from the tertiary care hospital were screened for these Hb (Hemoglobin) variants. The complete blood counts were analyzed in an automated Hematology analyzer (pocH- 100i, SYSMEX). The CBC of the samples was analyzed using an automated cell counter (SYSMEX) within 24 hours of blood collection. The Hb variants were diagnosed using the Hemoglobin Typing Machine (D 10, BioRad). The chromatograms were analyzed and Hb variants were identified and diagnosed.

Results

The Hematological parameters varied depending on the Hb variants the individual was diagnosed with. Most cases with Hb variants were Anemic with variations in Mean Cell Volume (MCV), Mean Cell Hemoglobin (MCH). The Hematological features of the study subjects are shown in Table 1. The Hemoglobin typing test was done and it was observed that out of the total 1118 cases tested, 698 (62.43%) were positive for Hb variants like β-Thalassemia minor (16.99%), β-thalassemia major (2.32%), Hb E heterozygous (22%), Hb E homozygous (6.62%), Sickle cell trait (3.04%), Sickle cell disease (1.69%), Compound Hb E-β Thalassemia (9.66%) and Compound Hb S-βThalassemia (0.1%) (Table 2). The rest 37.57% were not detected without any Hemoglobinopathies or Thalassemia.

Discussion

It is seen that with a prevalence rate as high as 62.43%, Hemaglobinopathies and Thalassemia is a serious issues among the people of Assam, India. Though previously the HbE and beta Thalassemia were confined to only a few tribes and restricted to a few populations, our study suggests that these Hb variants occur in other populations too nowadays. These may be because of the non-adherence to strict intra-caste marriage norms and the migration of people worldwide.

Beta Thalassemia and Compound Hb E-beta Thalassemia are more serious because the patients are mostly transfusion dependent. The transfusion-dependent patients are a burden to their families and society too. But a lack of knowledge regarding the prevalence of these types of genetic Hemoglobin disease, the inability to carry out genetic counseling, and the presence of only a few centers for prenatal diagnosis have failed in community control of the birth of these preventable genetic disorders.

Conclusion

In Assam too, there are very less community-based screening schemes, and only a few awareness programs are held. So people are unaware of these genetic diseases. There are only a very few centers that assist in prenatal diagnosis. As we know that transplantation can be done to cure, but it is not affordable for everyone. So, with a more than 50% occurrence rate, more studies related to genetic Hemoglobin diseases should be conducted for comparison and better assessment of the scenario.

As an urgent need, to curb this genetic Hemoglobin disease, our Government should take more steps to establish programs. The most effective approach to reducing the burden of society is to reduce the incidence by implementing a carrier screening program, offering genetic counseling, prenatal diagnosis, and selective termination of pregnancy of the affected fetuses in India. As like in other countries, in India also, we can diagnose early, and treat and cure genetic Hemoglobin disease, with health awareness programs and counseling.

Declarations

Conflict of Interest

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Acknowledgment

The authors are thankful to DBT, Govt. of India for the financial support.

References

1. Tawfik, S. A., et al. "Influence of Feeding Onion Waste on Some Blood Components and Rumen Parameters Of Sheep." Assiut Veterinary Medical Journal, Vol. 55, No. 120, 2009, pp. 1-16.
   Google Scholar
2. Pathak, Mauchumi S., Monalisha S. Borah, and Dulal Kalita. "Haemoglobin S Interaction with Beta Thalassaemia-A Case Report from Assam, India." Journal of clinical and diagnostic research, Vol. 8, No. 9, 2014, p. FD15.
   Google Scholar     Crossref
3. De-Gruchy G.C. "ClincialHematology in Medical Practice," 4th edn,1985; New Delhi.
4. Thompson, Ronald B., and Lionel E. H. Whitby. "Disorders of the blood: a textbook of clinical haematology." Churchill Livingstone, Vol. 475, 1977.
   Google Scholar    
5. Galanello, R., et al. "Prevention of thalassaemia and other hemoglobin disorders, Vol. 1." Thalassaemia International Federation Publications, Nicosia, Cyprus 2003.
   Google Scholar
6. Balgir, R. S. "The burden of haemoglobinopathies in India and the challenges ahead." Current Science, 2000, pp. 1536-47.
   Google Scholar    
7. Goldbloom, Richard B. "Screening for hemoglobinopathies in Canada." The Canadian Task Force on the periodic health hxamination. The Canadian guide to clinical preventive health care. Ottawa: Public Health Agency of Canada, 1994, pp. 206-18.
   Google Scholar
8. WHO "Thalassaemias and Other Hemoglobinopathies:" Prevalence of Haemoglobinopathies," 118th session, 2016, pp. 1-8.
   Google Scholar
9. Farhangi, Mehdi, Martin D. Sass, and Arthur Bank. "Prolonged Survival in Homozygous High A2�Type Beta Thalassaemia." Scandinavian Journal of Haematology, Vol. 7, No. 6, 1970, pp. 465-70.
   Google Scholar     Crossref
10. Lukens, J. N. "The abnormal hemoglobins: general principles." 1st edn, Wintrobe’s clinical hematology, 1999.
    Google Scholar
11. Mukherjee, B. N., et al. "Population genetic study in ten endogamous groups of West Bengal, India." Anthropologischer Anzeiger, 1987, pp. 239-54.
    Google Scholar     Crossref
12. Balgir, R. S. "The burden of haemoglobinopathies in India and the challenges ahead." Current Science, 2000, pp. 1536-47.
    Google Scholar    
13. Krishnamurti, Lakshmanan. "Few Reports of Hemoglobin E/β-Thalassemia in Northeast India: Underdiagnosis or Complete Exclusion of β-Thalassemia by Hemoglobin E." Journal of pediatric hematology/oncology, Vol. 22, No. 6, 2000, pp. 558-63.
    Google Scholar     Crossref
14. Sengupta, M. "Thalassemia among the tribal communities of India." Internet Journal of Biological Anthropology, Vol. 1, No. 2, 2008.
    Google Scholar
15. Agarwal, M. B. "The burden of haemoglobinopathies in India--time to wake up?." The Journal of the Association of Physicians of India, Vol. 53, 2005, pp. 1017-18.
    Google Scholar    
16. Papiha, S. S., et al. "Some hereditary blood factors of the Bengali Muslim of Bangladesh (red cell enzymes, haemoglobins, and serum proteins)." Humangenetik, Vol. 28, No. 4, 1975, pp. 285-93.
    Google Scholar
17. Vichinsky, Elliott. "Hemoglobin E syndromes." ASH Education Program Book, Vol. 2007, No. 1, 2007, pp. 79-83.
    Google Scholar     Crossref
18. Deka, R., et al. "Hemoglobinopathies in northeast India." Hemoglobin, Vol. 11, No. 5, 1987, pp. 531-38.
    Google Scholar     Crossref
19. Deka, R., et al. "Hemoglobin E distribution in ten endogamous population groups of Assam, India." Human heredity, Vol. 38, No. 5, 1988, pp. 261-66.
    Google Scholar     Crossref
20. Das, Bhaskar, and Sarthak Sengupta. "RETRACTED: HbE genotypes and fertility: A study on a Tibeto-Burmese population in Upper Assam, India." Annals of human biology, Vol. 35, No. 4, 2008, pp. 422-31.
    Google Scholar     Crossref
21. Baruah, Mrinal K., Malavika Saikia, and Aditi Baruah. "Pattern of hemoglobinopathies and thalassemias in upper Assam region of North Eastern India: high performance liquid chromatography studies in 9000 patients." Indian Journal of Pathology and Microbiology, Vol. 57, No. 2, 2014, pp. 236-43.
    Google Scholar     Crossref
22. Borah M.S., Pathak M.S., Bhattacharya PK, "Occurrence of haemoglobinopathies and thalassaemia in North-east India- a hospital based study." Online Journal of Biosciences and Informatics, Vol. 5, No. 1, 2013, pp. 397-406.
23. Pathak, Mauchumi S., M. S. Borah, and Dulal Kalita. "Disorders of Hemoglobin variants in Paediatric Patients attending in a tertiary care hospital of Northeast India." International Journal of Biological and Medical Research, Vol. 5, No. 1, 2014, pp. 3841-46.
    Google Scholar    
24. Balgir, R. S. "The burden of haemoglobinopathies in India and the challenges ahead." Current Science, Vol. 79, No. 11, 2000, pp. 1536-47.
    Google Scholar    
25. Balgir, R. S. "Control and prevention of the genetic load of haemoglobinopathies in India." National Medical Journal of India, Vol. 12, No. 5, 1999, pp. 234-38.
    Google Scholar