[reacharavindh]

Two thoughts came rushing to my mind after reading this.

Disclaimer: I have not researched the scientific background of these thoughts. They are mere thoughts.

It made me uncomfortable to read about the autistic child at the end of the story. Was Autism more probable because of the closer genetic relationship of parents?

I was raised in southern India, and some of our families have a fascinating astrological tradition about not marrying someone from same "Gothram".

https://en.m.wikipedia.org/wiki/Gotra

Is it possible that our ancestors knew that certain genetic combinations were unhealthy/undesirable even without a scientific background and adopted these rules for the society?

[mindentropy]

I am from India(South) and also coming from a family where there are quite a lot of people in the medical field.

Yes it was known not to marry inside the family by our ancestors. I know several people who are suffering from various birth defects due to marrying very close and inside the family and yes it is told by the doctors.

Gotra is completely screwed up now. A system has to be taken seriously. If a person doesn't know his Gotra then he is just arbitrarily assigned one which becomes dangerous when done in huge volumes.

Also in India there are caste communities which are smaller and when they have to marry inside their families problems start cropping up.

There is a huge demand for home nurses and speech and hearing specialists in the Gulf region. This is because of consanguineous marriages very prevalent there. There are a lot of children born with mental or speech disabilities.

[eesmith]

Nearly every culture has taboos on incest. https://en.wikipedia.org/wiki/Incest comments "sexual relations with a first-degree relative (such as a parent or sibling) are almost universally forbidden".

If you were Christian you would point to Leviticus 18:6-18 for the Biblical definition of incest. https://www.biblegateway.com/passage/?search=Leviticus+18%3A... .

As the Wikipedia page I linked to further states: "cultural anthropologists have noted that inbreeding avoidance cannot form the sole basis for the incest taboo because the boundaries of the incest prohibition vary widely between cultures, and not necessarily in ways that maximize the avoidance of inbreeding."

The further refinement of your question might be, how do the unique aspects of the astrological tradition affect inbreeding?

In order to test your hypothesis you would need to define gotras. I will quote from the Wikipedia page you linked to:

> the definition of gotra as descending from eight sages and then branching out to several families was thrown out by the Bombay High Court. The court called the idea of Brahmin families descending from an unbroken line of common ancestors as indicated by the names of their respective gotras "impossible to accept." The court consulted relevant Hindu texts and stressed the need for Hindu society and law to keep up with the times, emphasising that notions of good social behaviour and the general ideology of the Hindu society had changed. The court also said that the mass of material in the Hindu texts is so vast and so full of contradictions that it is a near-impossible task to reduce it to order and coherence.

[uvesten]

It is a fact, not a possibility. That's (a big part of) the reason that incest is a taboo in all cultures.

[gadders]

Sadly not all societies/cultures have a taboo against incest:

"Couples who are getting married should be forced to have a DNA test first to ensure they are not cousins amid growing concern about incest within Pakistani communities, Britain's first Asian peer has claimed."

https://www.telegraph.co.uk/news/health/children/11723308/Fi...

[EDIT] Additional link from the BBC today: https://www.bbc.co.uk/news/stories-46558932

[fouc]

>Third-degree relatives (such as half-aunt, half-nephew, first cousin) on average share 12.5% genes, and sexual relations between them are viewed differently in various cultures, from being discouraged to being socially acceptable.

Relationships between cousins isn't always considered to be incest. It's more recent in the last 50-60 years, especially in USA, that cousin marriage is frowned upon based on misunderstanding the risk.

[Veen]

But is that risk not increased when the family has practiced cousin marriage for many generations?

[gadders]

It's not legally incest, but it's not a good idea.

[distant_hat]

The other issue there is people who are related by multiple lineages. I know a family where the brothers married 2 sisters. Technically, their kids are cousins, but genetically they are siblings. Do enough of that and your genetic diversity of a community goes down to the point recessive diseases start showing up.