Parents of the same blood type have disabled children?
September 9, 2013 6:29 AM   Subscribe

What is the historical/scientific background for the theory that it is problematic for individuals of the same blood type to have children, and that it will lead to disability in the child? I have come across this idea several times from individuals from (I think) India or Bangladesh.

Did the myth develop to dissuade consanguinous relationships and their genetic disorders? Perhaps it is related to problematically rare blood types (Bombay Blood Group), which is a situation that may not be as salient elsewhere?

I know nothing about this subject, but I've seen it come up enough, and seen so many patronizing dismissals of people's concerns (or repeated semi-unrelated explanations of +/- Rh incompatibility), that I became curious about the background of such a specific idea. I also can't imagine the history of this theory going back overly-far, considering the specifics of blood testing and semi-short history of blood groups, etc. I also know that sometimes a myth is just a myth, but this one seems so very specific.

Many thanks for any background related to the subject.
posted by thegreatfleecircus to Society & Culture (7 answers total)
 
Perhaps it's due to correlation = causation fallacies? When people do share inherited elements that lead to disabilities in their children, it's probably more likely that they also have the same blood type? And blood type is a highly visible personal attribute, as opposed to some obscure genomic combination.
posted by ubiquity at 7:17 AM on September 9, 2013


There is truth to the RH +/- concerns, which may or may not be keeping other myths about blood type alive. And RH+ or RH- is a part of blood type (O+, O-, etc. the + or the - refers to the RH factor).

If a pregnant woman and her fetus have an RH incompatibility, it can lead to difficulties.

Fortunately, there's a simple shot that usually takes care of the problem in first world countries. However, in parts of India and Bangladesh, it's entirely possible this simple shot isn't available as easily or without some expense, so it may be possible the blood type myths you are encountering are related to this.

If you're speaking specifically as to why a person with blood type A shouldn't have a baby with a person who has blood type O, then I can't really speak to that, except that it seems a very strong possibility that the general myth around blood types is continuing due to a misunderstanding of the RH factor.
posted by zizzle at 7:32 AM on September 9, 2013


I also know that sometimes a myth is just a myth, but this one seems so very specific.

It's always seemed, to me, to be pretty similar to "oh I can't date him, he's a Scorpio, you know what THEY'RE like."

There's some history about the probable origins of this stuff on Wikipedia:

In 1926, Rin Hirano and Tomita Yashima published the article "Blood Type Biological Related" in the Army Medical Journal. It was seen to be a non-statistical and unscientific report, motivated by racism.

In 1927, Takeji Furukawa, a professor at Tokyo Women's Teacher's School, published his paper "The Study of Temperament Through Blood Type" in the scholarly journal Psychological Research. The idea quickly took off with the Japanese public despite Furukawa's lack of credentials, and the militarist government of the time commissioned a study aimed at breeding ideal soldiers. The study used ten to twenty people for the investigation, therefore failing to meet the statistical assumptions required to demonstrate that the tests were either reliable or generalisable to the wider population.

In another study, Furukawa compared the distribution of blood types among two different ethnic groups, the Formosans in Taiwan and the Ainu of Hokkaidō. His motivation for the study appears to have come from a political incident: After the Japanese occupation of Taiwan following Japan's invasion of China in 1895, the inhabitants tenaciously resisted their occupiers. Insurgencies in 1930 and in 1931 resulted in the deaths of hundreds of Japanese settlers.

The purpose of Furukawa's studies was to "penetrate the essence of the racial traits of the Taiwanese, who recently revolted and behaved so cruelly". Based on a finding that 41.2% of a Taiwanese sample had type O blood, Furukawa assumed that the Taiwanese rebelliousness was genetically determined. The reasoning was supported by the fact that among the Ainu, whose temperament was characterized as submissive, only 23.8% had type O. In conclusion, Furukawa suggested that the Japanese should increase intermarriage with the Taiwanese to reduce the number of Taiwanese with type O blood.

Interest in the theory faded in the 1930s as its unscientific basis became evident. It was revived in the 1970s with a book by Masahiko Nomi, a lawyer and broadcaster with no medical background. Nomi's work was largely uncontrolled and anecdotal, and the methodology of his conclusions was unclear. Because of this, he was heavily criticised by the Japanese psychological community, although his books remain popular. His son continued to promote the theory with a series of books, and by running the Institute of Blood Type Humanics.

posted by showbiz_liz at 7:37 AM on September 9, 2013 [1 favorite]


No idea at all if this is where the theory about blood types in particular is coming from, but bouncing off the 'he's a scorpio' idea, it's worth noting that the Ayurvedic personality/body type system emphasizes balance - roughly, if you are a hot/wet type, you need foods, mindsets, and activities that emphasize things that are metaphorically (or actually) cool & dry. So I can imagine (but have no specific evidence for) that if you introduce the idea of biological blood types to an existing Ayurvedic theory, the expectation would be that you similarly want to pair 'like with unlike' rather than 'like with like.'
posted by heyforfour at 8:31 AM on September 9, 2013


Myth. Like zizzle said, the Rh part of the blood type is significant, and someone is probably extrapolating from Rh issues to ABO.

I grew up in India, but I never heard anyone say this, at least in the urban north.
posted by phliar at 1:06 PM on September 9, 2013


Response by poster: For the record, I know the Rh is important and relevant. But I don't get the impression that it has anything to do with this myth. It's the opposite of this issue. But yes, people love to bring it up in response to the specific concern about the *same* blood type. I guess there isn't much info about this, thanks for the ideas though.
posted by thegreatfleecircus at 5:58 PM on September 9, 2013


While this wasn't my culture area (I only took one class that had a lot of SE Asia/sub-continent content), I did some poking around because I am interested in the health/anthropology combination. So I've got some conjecture, with the qualification that while I am/was an anthropologist, I am not one who works in this region at all.

I'm wondering if the phrase 'blood type' is a sort of folk-definition or shorthand in English for the various types of 'blood relation' which exist in various cultures in the region. One author, Lina Fruzzetti, wrote a lot about 'blood' and what a 'blood relative' is of various types in Bengali culture (and in contrast to some other regions as well.) Eg, "blood being a category that is constituted differently for [the regions of Bengal and Tamilnadu]." (Fruzzetti, 'The cultural construction of the person in Bengal and Tamilnadu') It looks like some 'blood' lines are what we would think of as 'blood relatives', whereas others are kinship lines that follow men only, can be transitive for women, and/or have relationships to symbolic relatives, castes, sub-castes, and so on. So 'exogamy', or marrying outside these lines, however they were defined, was important. The result of disobeying marriage rules could be death, incurable disease 'or other calamity', both to the wife and any children or possibly the household in general. Modern English could subsume these into 'blood types' by folk usage of the term, which doesn't necessarily line up with our definition of it (ABO/Rh/Kell/Duffy etc.)

That said, I my initial thought was that 'blood type' was a folk usage of the term to define all genetic-linked diseases, such as thalassemia, sickle-cell, or something else that would make a child 'sickly' and could be the result of similar 'blood types' in a folk-etymology of the term.

Following a hunch, the thalassemia connection is made by a researcher who says " Blood is so deeply valued in the Bengali kinship system that this genetic mutation is perceived to be corrupting the blood (rakter dosh). Being a thalassemia carrier (i.e., having thalassemia minor) renders an individual unfit as a suitable marriage partner because of beliefs related to purity of blood, its association with the continuity of the lineage, and subsequent transmission of desirable traits to future generations." (Chattopadhyay, S. (2006). ‘Rakter dosh’—corrupting blood: The challenges of preventing thalassemia in Bengal, India. Social Science & Medicine, 63(10), 2661-2673.)

So while I couldn't find a 'blood type = disabled children' per se, there are a lot of cultural beliefs about blood lines, which don't necessarily translate easily, as well as about corruption of blood via disease (acquired or genetic abnormalitiy), which predispose attitudes towards marriage prohibitions.
posted by cobaltnine at 9:52 PM on September 9, 2013


« Older Copying Mozilla Firefox Preferences   |   How do you teach values (I'm not talking about... Newer »
This thread is closed to new comments.