History - Fitting in the Genes

How old are we Indians?

This might be a silly question to ask in the age of light-speed internet. However, once you start thinking about it, you begin to realise that the question is not so silly after all. It is important precisely because half-baked analysis does indeed travel at light-speed, colouring the way we differentiate ourselves from 'others'. It becomes the basis for identity-based politics on the basis of which political power is being consolidated in our times.

Tony Joseph's book "EARLY INDIANS - The Story of Our Ancestors and Where We Came From" (Juggernaut 2018) is a bit like a probing needle that seeks to burst some of these inflated balloons of identity-based politics. Tony is a journalist makes no pretence of being a neutral observer and reporter. Scroll down his tweets (@tjoseph0010) and you realise that he has his axe to grind against the 'Hindutva Brigade' of India's right wing. But fact is that he is also a good story teller.

One generation ago, school history books told us that Radio Carbon Dating was one of the scientific tools used to unravel the story of human origins and migrations. From what we can see, despite all the scientific progress that has been made over the past 30 years, the narrative in text-books remains unchanged. Tony gathers up all the latest available scientific data, not only from RCDating but also genetics, linguistics, geology and biochemistry to tell us the story of our origins.

The main protagonists in his story are -

• mtDNA - Mitochondrial DNA which remains outsider the nucleus, and is inherited exclusively from the mother. "If you go back 10 generations you will have 1024 people who you can call your ancestor, but your mtDNA  or Y-chromosome would have any connection with only 10 of them"
• Y-chromosome / Y-DNA - inherited exclusively from the father.  Oldest branches in Y-chromosome are 0 A, B, CT and D
• Gene Mutations - to create genetic family trees, and to work out the approximate time that has passed since two branches of a tree diverged
• Haplogroups (Gk Haplo=single) - branches of the mtDNA and Y-DNa family trees -- parent branch is called 'macro-haplogroup', sub-haplogroups or "clades" refer to sub-branches. Oldest branches in mtDNA are haplogroups L0, L1, L2 and M7

The story that emerges from this wide range of sources is that even though the earliest evidence of humans habitation in India dates back to 1.5 million years, from Palaeolithic tools found at Attirampakkam in Tamil Nadu (69km from Chennai), modern humans (Homo sapiens) came in much, much later.

Mitochondrial DNA (mtDNA from females) haplogroup M2 is the most ancient one in the Indian subcontinent. This group arose around 60,200 years ago and is rarely found outside South Asia.  70-90% of mtDNA haplogroups in India can trace their origins to the First Indians who arrived in India around 65,000 years ago, while only 10-30% of remaining mtDNA lineages is from later migrations. However when it comes to paternal ancestry the tables turn. Only 10-40% of Y-chromosome haplogroups is from the First Indians while the remaining 60% came from males coming in later migrations.

Connect the dots with archeological evidence and the following timeline merges -

• 300,000 years - remains of the modern human - Homo aspens - found in a cave in Jebel Irhoud, 50km from the city of Safi in Morocco
• 180,000 yrs - Rock shelter in Misliya north Israel - first human fossil outside Africa
• 70,000 yrs - Geneticists calculate Out of Africa (OoA) migration
• 7000 BCE - Mehrgarh, agricultural settlement found at the foothills of the Bolan hills in Baluchistan
• 7000 BCE - evidence of rice harvesting at Lahuradewa in the Sant Kabir Nagar dish of Uttar Pradesh in the Upper Ganga plain
• 5500 - 2600 BCE - the Early Harappan era
• 2600 - 1900 BCE - the Mature Harappan period
• 2300-1700 BCE - the Bactria-Margiana Archaelogical Complex (BMAC) centred on the Oxus river (Amu Darya)
• 2100 BCE - a southward migration of pastoralists from the Kazakh Steppe towards the central Asian regions...and then to South Asia

It is amazing to think that at the time of the earliest Harappan settlements in 5500 BCE, the Indian subcontinent modern humans who had been living across the country for over 60,000 years. Not only did these early settlers spread across the peninsula (at least in coastal areas), but also migrated all the way across South East Asia to Australia!

In other words, long before the Vedic Aryans migrated to India from the steppes of Central Asia, with their horses and numerous Gods, this region had been home to people who had their own unique languages and belief systems. It is the blending of all these diverse streams that makes India what it is today.

On the whole Tony Joseph's narrative is interesting but not quite convincing. It is not clear if adequate samples of mtDNA and Y-DNA were collected during the studies citied in the book. One also wonders why a book citing research papers in 2018 fails to mention the recent finding of an ancient chariot in Sanauli (Uttar Pradesh) from the Bronze-Copper Age, dating back to 2000 BCE - 1800 BCE.

How do we reconcile the absence of horse-drawn vehicles in Indus Valley civilization with their presence in the Gangetic Plains? I hope to see many more books like 'Early Indians' that unravel the mysteries in this part of the world.

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REFERENCES & LINKS

Book - Joseph, Tony (2018): EARLY INDIANS - The Story of Our Ancestors and Where We Came From, Juggernaut, New Delhi 2018

The Sanauli Charriot -  https://www.indiatoday.in/india/story/indians-used-chariots-4-000-years-ago-asi-unearths-evidence-in-up-1251650-2018-06-06

Our Genes

In the Mahabharata epic, there is a poignant exchange that takes place after the Great War, between the eldest of the Pandava princes, Yudhistira, and a forest spirit. A quiz in metaphysics is the price demanded by the Spirit for reviving Yudhistira's siblings who have died of thirst and poisoning.

One of the questions is: 'What is the greatest wonder in the world?'
And Yudhistira's reply is : "People die everyday and those who are alive go on as though they will live for ever!"

Siddhartha Mukherjee's books seems to capture this profound irony in his first book, "Emperor of All Maladies" and then again, in his latest book, "The Gene". A 'normal' healthy body and mind is something most of us take for granted - even as an entitlement - until something happens to us, or to our own close friends or relatives that brings us face to face with the fragility of life itself.

The great advances in science & technology lull us into a false sense of security - until raconteurs like Mukherjee tell us about the heroic efforts, pain and serendipity that underpin each and every invention that mark our progress, as well as the huge lacunae in our own understanding of the world around us, and within us.

Here are a couple of shockers that hit me while reading "The Gene"

There are more than 2500 different genetic defects that have been recorded to date. Most of them are like simple spelling mistakes that end up destroying lives, across generations.

Take the case of Sickle Cell Anemia. It is the result of a single change in one triplet in our DNA. The sequence GAG gets changed to GTG. This results in the substitution of one amino acid for another: glutamate gets switched to valine, thus altering the folding of the hemoglobin protein chain. As a result protein debris gets accumulated in string like clumps in our red cells; they are unable to glide smoothly through our blood capillaries, and get jammed into microscopic clots throughout the body, interrupting the flow of blood, and resulting in excruciating pain, like corkscrews being drilled into our bones.

Then there is Huntington's Chorea. It is the "opposite of a dance, a joyless pathological caricature, the ominous manifestation of dysregulated brain function".

In 1992 researchers tracked the disease down to one gene called “interesting transcript 15” (IT15). This gene was found to encode an enormous protein - a biochemical behemoth containing 3,144 amino acids, larger than any protein in the human body (insulin has a mere 51 amino acids). And yet, beyond the fact that this protein is found is our neurons and testicular tissue, we know nothing about its actual role in our bodies, let alone why it causes a debilitating disease...

The Gene puts the Spirit's question and Yudhistira's answer into completely new perspectives.