Geneticists: What Does the “Bombay Blood Group” Show About Migrations?

 

Geneticists: What Does the “Bombay Blood Group” Show About Migrations?

Shrikant G. Talageri 

 

Watching TV serials can be very frustrating for people like me who cannot adopt a detached attitude and who get easily irritated by the illogical, pseudo-saintly and plainly stupid behavior of the characters (obviously only the “good” characters behave in these ways) in the serials. I have only started tentatively and sporadically watching a few Marathi serial episodes when I have nothing else to do and the TV is on.

But sometimes interesting and useful information can come from anywhere, even from these generally stupid serials. Today I came to know about a blood group called the “Bombay Blood Group” which is apparently an extremely rare blood type.

Having never heard of this blood group before, I hastened to check up on Google, and got the following information:

“The Bombay blood group (hh) is an extremely rare blood type, first found in Mumbai, India, where individuals lack the essential H antigen (precursor) needed to form A or B antigens, making them appear as O but unable to receive any standard A, B, AB, or O blood; they can only receive blood from other Bombay (hh) donors, requiring special awareness for transfusions.  

Key Characteristics

Absence of H Antigen: 

The fundamental issue is a mutated gene preventing the creation of the H antigen, a base for A & B antigens. 

Anti-H Antibodies: 

Bombay individuals produce strong anti-H antibodies, which attack any blood cells with the H antigen (which is almost all blood, including O)”

 

What is interesting is the distribution of this blood group, which is found primarily in India, and which, on a specific question being asked, received the Google AI Overview reply: “Yes, the Bombay blood group (also known as the hh phenotype) originated in India”.

This blood group is found primarily in India: “It is significantly more common in India than in the rest of the world, with a prevalence of approximately 1 in 10,000 individuals. It is most frequently found in states such as Maharashtra, Karnataka, and Andhra Pradesh.

Global Rarity: Globally, it is extremely rare, occurring in only about 1 in 1,000,000 people outside of South Asia.”

Which in fact are the areas of the world where this blood group is almost absent? Specific inquiries about Native America, Africa and Aboriginal Australia produced the following information:

“North America: The phenotype has been reported in individuals of Indian descent in the US but is not indigenous to the general population.”

“The Bombay blood group is found predominantly in the Indian subcontinent and is extremely rare in people of African descent, with some studies in Africa showing a zero prevalence rate.”

“It is generally considered extremely rare in other populations, including Australian Aboriginals, while individuals with the Bombay blood group may be seen in countries like Australia due to the Indian diaspora.”

So this is clearly a blood type basically restricted to what we may roughly call the Eurasian landmass, consisting of Asia and Europe.

In Asia and Europe, what are the proportions in which this blood group is found?

1. In India: To repeat some of this, “It is significantly more common in India than in the rest of the world, with a prevalence of approximately 1 in 10,000 individuals. It is most frequently found in states such as Maharashtra, Karnataka, and Andhra Pradesh.”

But “In certain regions of India, such as Mumbai and parts of southern and western India, the frequency can be even higher, sometimes reported as high as 1 in 4,500 people or up to 1 in 278 among specific tribal populations.”

It is found in the highest proportion in the Bhuyan tribes of Orissa: “2 out of 244 Khandayat Bhuyan and 1 out of 379 Paudi Bhuyan from Hemgiri and Lahunipara blocks, respectively, in the Bhuyan tribe of Sundargarh district in North-Western Orissa were detected, giving an incidence of 1 in 122 in Khandayat Bhuyan and 1 in 379 in Paudi Bhuyan, with an average of 1 in 278 among the Bhuyan tribal population.”

2. In Southeast Asia: The general proportion is similar to India: “Cases have been reported in countries like Malaysia, Thailand, and Taiwan. The general incidence rate in the region is often cited around 1 in 10,000 individuals.”

3. In China: “The Bombay blood group (Oh phenotype) is extremely rare in the general Chinese population, with an estimated proportion of roughly 1 in 10,000 to 1 in 100,000 individuals.”

“In Japan: Studies indicate the incidence of Bombay and para-Bombay phenotypes combined is about 1 to 2 in 300,000 people, showing its rarity even in East Asia. 

In Korea: The standard Bombay phenotype (hh) appears to be virtually non-existent or extremely rare, with researchers noting the absence of prior reports, as highlighted in the first Korean case report of the para-Bombay type.”

4. In Iran: “a reported prevalence of approximately 0.0008% in the general population of Iran (about 1 in 125,000 individuals)”.

In Arab West Asia: “While information for every Arab nation is not specifically available in large-scale studies, the general incidence in the Middle East region is considered very low, similar to the global average”

5. In Central Asia, Europe, and the Caucasus Region:

“While specific data for all individual Central Asian countries (e.g., Kazakhstan, Uzbekistan, etc.) is not readily available in the search results, the general global trend suggests the proportion would likely be very low, more in line with the European or general global figures”

“In the general European population, it is about 1 in 1,000,000” including among the Basque people: “consistent with general European rarity, despite Basque genetic distinctiveness”

“The Bombay blood group is extremely rare in the Georgian population, with an estimated frequency of approximately 1 in 1,000,000 individuals, consistent with the general European population.”

 

So we see a clear radiation of the frequency of this rare blood group:

1. Eastwards, from 1 in 10,000 (going to as high as 1 in 278 in certain parts) in India (east, south and west) and also from 1 in 10,000 in Southeast Asia, to around 1 in 100,000 in China and even lower proportions further east and north.

2. Westwards, from 1 in 125,000 in Iran, to around 1 in 1000,000 northwards  in Central Asia, Arab West Asia, the Caucasus region and Europe.

I have never doubted that genes can indicate migrations of people. But I totally reject the idea that genes can indicate the migrations of languages, especially when these claims go against the evidence of linguistic data and dated records. Here, I am just placing this data about this specific blood group, which shows that people from India migrated in all directions in ancient times, into different parts of Asia and Europe, but not into Africa, Australia or the Americas. I leave it to other scholars to decide if, and how far and in what respects, this is of any historical importance.