Gotra – A Scientific Reasoning

In the last article on Gotra we read about what is a Gotra, what are the various Gotra’s. In this write up let’s analyze why these Gotra’s were established and what is its scientific rationale. We all know that most Hindu families, marriage within the same gotra is prohibited since people with same gotra are siblings. Let’s look at reasons why this has been the practice for thousands of years amongst Sanatana Dharma. Gotra is always passed on from father to children among most Hindus, just like last name(surname) is passed on worldwide. Additional rule in the Gotra system is that, even if the Bride and Bridegroom belong to different Gotras, they’ still cannot get married even if just one of their Gotra Pravara matches.

It is generally a well accepted norm that women after marriage not only carry the last name of their spouse but also their Gotra. Why would they do this? Is there any scientific rationale for this practice which to many modern liberal thinker’s reeks of Male dominance. Truth is that its anything but that. Let’s analyze this further.

Genes & Chromosomes

Humans have 23 pairs of Chromosomes and in each pair one Chromosome comes from the father and the other comes from the mother. So, in all we have 46 Chromosomes in every cell, of which 23 come from the mother and 23 from the father.

Of these 23 pairs, there is one pair called the Sex Chromosomes which decide the gender of the person. During conception, if the resultant cell has XX sex chromosomes, then the child will be a girl and if it is XY then the child will be a boy. X chromosome decides the female attributes of a person and Y Chromosome decides the male attributes of a person.

When the initial embryonic cell has XY chromosome, the female attributes get suppressed by the genes in the Y Chromosome and the embryo develops into a male child. Since only men have Y Chromosomes, son always gets his Y Chromosome from his father and the X Chromosome from his mother. On the other hand, daughters always get their X Chromosomes, one each from both father and mother.

So, the Y Chromosome is always preserved throughout a male lineage (Father – Son – Grandson) because a son always gets it from his father, while the X Chromosome is not preserved in the female lineage (Mother, Daughter, Grand Daughter) because it comes from both father and mother. A mother will pass either her mother’s X Chromosome to her Children or her father’s X Chromosome to her children or a combination of both because of both her X Chromosomes getting mixed (called as Crossover). On the other hand, a son always gets his father’s Y Chromosome and that too almost intact without any changes because there is no corresponding another Y chromosome in his cells to do any mixing as his combination is XY, while that of females is XX which hence allows for mixing as both are X Chromosomes.

Women never get this Y Chromosome in their body. And hence Y Chromosome plays a crucial role in modern genetics in identifying the Genealogy ie male ancestry of a person. And the Gotra system was designed to track down the root Y Chromosome of a person quite easily. If a person belongs to Kashyapa Gotra then it means that his Y Chromosome came all the way down over thousands of years of timespan from the Rishi Kashyap.

This is also the reason why females are said to belong to the Gotra of their husbands after marriage. That is because women do not carry Y Chromosome, and their Sons will carry the Y Chromosome of the Father and hence the Gotra of a woman is said to be that of her husband after marriage.

Shrinking size of Y Chromosome

Y is the only Chromosome which does not have a similar pair in the human body. The pair of the Y Chromosome in humans is X Chromosome which is significantly different from Y Chromosome. Even the size of the Y Chromosome is just about one third the size of the X Chromosome. In other words, throughout evolution the size of the Y Chromosome has been decreasing and it has lost most of its genes and has been reduced to its current size. Scientists are debating whether Y Chromosome will be able to survive for more than a few million years into the future or whether it will gradually vanish, and if it does so whether it will cause males to become extinct! Obviously because Y Chromosome is the one which makes a person male or a man.

A Y Chromosome must depend on itself to repair any of its injuries and for that it has created duplicate copies of its genes within itself. However, this does not stop DNA damages in Y Chromosome which escape its local repair process from being propagated into the offspring males. This causes Y Chromosomes to accumulate more and more defects over a prolonged period of evolution and scientists believe that this is what is causing the Y Chromosome to keep losing its weight continuously.

Y Chromosome which is crucial for the creation and evolution of males has a fundamental weakness which is denying it participation in the normal process of evolution via Chromosomal mix and match to create better versions in every successive generation, and this weakness MAY lead to the extinction of Y Chromosome altogether over the next few million years, and if that happens scientists are not sure whether that would cause males to become extinct or not. And that is because Scientists are not sure whether any other Chromosome in the 23 pairs will be able to take over the role of the Y Chromosome or not.

Now let’s look at a very contentious issue. Will humanity survive or it really does not matter if Males become extinct? The reality really may be that the females do not need the Y Chromosome to survive after all. Since all females have X Chromosomes, it may be possible to create a mechanism where X Chromosomes from different females are used to create offspring, say like injecting the nuclei from the egg of one female into the egg of another female to fertilize it and that would grow into a girl child.

Theoretically one may ask a few scientific hypothetical questions:

a)    Will the human body choose to go only a X Chromosome route?

b)    Will the human genome pick another chromosome from the group of 23 to conceptualize foetal union? 

c)    Will that human be a more advanced version?

The bottom line is yes, there is a strong possibility that humanity may still exist with only Females and Males may go extinct after all. A grim reminder to all.

Gotra System helps to protect the Y Chromosome from becoming extinct

Its only now in the 20th Century that the modern-day scientists have concluded that children born to parents having blood relation (like cousins) can have birth defects. But keep in mind this was known to the Ancient Rishi’s thousands of years before. For example, lets assume if there is a recessive defective gene in a Male / Female. What this means is, this defective gene can be expressed in the child and may lead to serious birth defects. It is also possible this defective gene may not be expressed for many generations because the corresponding gene in the pairing Chromosome is stronger and hence is preventing this abnormality causing gene from activating.

Now there are fair chances that his offspring’s will be carriers of these genes throughout successive generations. If they keep marrying outside this genetic imprint, there is a fair chance that the defective gene will remain inactive since others outside this person’s lineage most probably do not have that defective gene.

Now if after 5-10 generations down the line say one of his descendants marries some other descendant carrying this defective gene, then there is a possibility that both are still carrying the defective gene. In that case their children will have the defective gene express itself and cause the genetic abnormality in them as both the Chromosomes in the pair have the defective genes. Hence, the marriages between cousins always have a chance of causing an otherwise recessive, defective genes to express themselves resulting in children with genetic abnormalities.

So, thank our Ancient Rishis for creating the Gotra system where they barred marriage between a boy and a girl belonging to the same Gotra no matter how deep the lineage tree was, in a bid to prevent inbreeding and eliminate all recessive defective genes from the human DNA.

All I can say is we have to be amazed at such insights coming from our Ancient Rishi’s thousands of years before the Modern-Day scientists had figured it out.