Bombay blood group: Is prevalence decreasing with urbanization and the decreasing rate of consanguineous marriage

Abstract

Context:Bombay blood group although rare is found to be more prevalent in the Western and Southern states of India, believed to be associated with consanguineous marriage.Aims:To estimate the prevalence of the Bombay blood group (Oh) in the urban population of Puducherry. To find the effect of urbanization on consanguineous marriage and to establish whether consanguinity plays a part in the prevalence of Oh group. To compare Oh group prevalence with that of other neighboring states, where population is not predominantly urban.Settings and Design:This is a descriptive study in a tertiary care hospital in Puducherry, over a period of 6 years.Materials and Methods:All blood samples showing ‘O’ group were tested with anti-H lectin. Specialized tests like Adsorption Elution Technique, inhibition assay for determination of secretor status were performed on Oh positive cases. Any history of consanguineous marriage was recorded.Statistical Analysis Used:All variables were categorical variable and percentage and proportions were calculated manually.Results:Analysis of the results of 35,497 study subjects showed that the most common group was ‘O’ group constituting 14,164 (39.90%) of subjects. Only three “Oh” that is, Bombay phenotype (0.008%) were detected. Consanguinity was observed in two cases (66.66%).Conclusions:This study shows the prevalence of Bombay blood group representing the urban population of Puducherry, to be high (0.008%) and associated with consanguineous marriage (66.66%). Thus, consanguinity is still an important risk factor present, even in an urban population in Southern India.

Prevalence of Bombay Blood Group Amongst the Healthy Blood Donors at a Tertiary Care Centre in Western Rajasthan, India

“…Balgir RS, [7] 2005, Orissa (Kutia Kondh tribe) 254 2 0.787 3 Verma A et al, [11] 2011, Tirupti A.P. 26638 4021 7M+6F 0.048 4 Kavitha A et al, [13] 2016, Chennai 8903 338 (33%) 2 0.022 5 Rudrappan RB & Veeran K, [14] 2016, Chennai 11512 2 0.017 6 Geetha RL et al, [12] 2011, Bangalore 37117 15032 (40.5%) 2M+4F 0.016 7 Mahapatra et al, [15] Mallick et al, [16] 2015, Puducherry 35497 (Both donors & recipients) 14164 3 0.008 9 Talukder et al, [17] 2014 , Kolkata 56465 28934 Donors 27531 Patients 6 2 4 0.011 0.007 0.014 10 Singh A et al, [18] 2019, Lucknow (Consanguinity in 2 cases of Bombay) 177888 5M+1F 0.003…”

Blood Diathesis in a Patient of Rare Blood Group ‘Bombay Phenotype’

“…The prevalence of Bombay phenotype is 1:10,000 in India however it is much less prevalent in the Caucasians with an incidence of 1:250,000 [4]. A study amongst an urban population in Puducherry, India demonstrated that 0.008% population had Bombay blood group and it was strongly associated with consanguineous marriage (66.66%) [5]. This prompts for pre-marital blood phenotyping for all individuals and discouragement of marriage amongst individuals carrying the h allele.…”

Bombay Blood Group and Pregnancy

“…Bombay blood type was known as the rarest in the world. The probability of finding a person with Bombay was one for every 250.000 worldwide ( 1 ). Bombay individuals was characterized by the absence of A, B and H antigens on red blood cells and associated with anti-H antibodies in plasma.…”