GENETICS OF THE INDIAN POPULATION:
This post is a continuation of my previous post Aryan Invasion & River Saraswati. This post discusses whether the Invasion caused an impact at all on the Indian population Genetics.
DNA mapping is used to chart human migrations. But first we need to understand a few Genetic terms. I am not an expert on Genetics, so I will keep the information only to what is needed.
Haplogroup:
A haplogroup is a genetic population group of people who share a common ancestor on their patrilineal or matrilineal line. Haplogroups are determined by specific genetic markers found in DNA, which are typically inherited from one’s parents. These genetic markers can be used to trace the ancestral migration patterns and origins of human populations. Haplogroups are often associated with either the Y-chromosome (Y-DNA haplogroups) or the mitochondrial DNA (Mt.DNA haplogroups).
- Y-DNA Haplogroups:
These are traced through the Y-chromosome, which is passed from father to son. Y-DNA haplogroups are used to study the paternal line and are typically used to trace the ancestry of males. They can provide insights into the migration and evolutionary history of male lineages.
R1a Haplogroup:
Haplogroups are usually represented by a letter or combination of letters and numbers, and they are often organized into a hierarchical structure. Haplogroup R1a is a well-known and widely studied Y-chromosomal haplogroup. It is one of the most prevalent Y-chromosomal haplogroups in Eurasia and is particularly common in regions such as Eastern Europe, South Asia, and parts of Central Asia. It is the world’s most successful extended family consisting of over a billion people. The oldest is the F haplogroup and as mutations occurred it progressed to R, then R1, then R1a and then R1a1a.
The most common Y-DNA haplogroup in Europe is R1b, which is further divided into subclades like R1b1a1a2a1a2b (often abbreviated as R-M269).
- (Mt.DNA) Haplogroups:
These are traced through mitochondrial DNA, which is passed from mother to all her offsprings. Mt.DNA haplogroups are used to study the maternal line and can provide insights into the migration and evolutionary history of female lineages.
Mt.DNA stays “outside” the cell nucleus as opposed to 46 Chromsomes (23 pairs) located “inside” the nucleus. Out of the 23 pairs of Chromosomes, 22 pairs are autosomal (meaning numbered or non-sex chromosomes) and one pair of sex chromosomes X & Y making it 23 pairs. Almost all genetic information is packed into these 23 chromosomes.
Essentially, all humans inherit their Mt.DNA from their mother but the father does not pass on Mt. DNA to their offspring. The father will only pass on the Y-Chromosome inherited exclusively from his father to his son. Thus the sex pair of chromosomes XX (female) and XY (male).
Conclusions:
- Human remains dating 300,000 years ago have been found in Africa. The first migration started 80,000 years ago from Africa into the outside world. Around 65,000 years ago, humans reached India further moved to Central Asia, South East Asia, Australia & Andaman Islands. These people are called Ancestral South Indians (ASI) and they spread over South & Central These early Indians are our ancestors!
Then they moved northward and mixed with people of Iran & Steppes (European) & Middle East and formed the Ancestral North Indian (ANI) group. Thus, everyone in India today is mixture of ANI & ASI groups. Population in India that has only ASI & only ANI has yet to be found. The mixing of both is evident as of now. <<<Click here to see an article from Harvard on Indian population mixture.
2. India has predominantly 70-90% Mt.DNA Haplogroup M-2 (Haplogroup M-1 remained in Africa. M-2 is a result of the mutation as migration happened to South Asia). Only 10-30% Mt. DNA is a result of later migrations. No major gene inflows took place from outside India in the last 12,500 years!
R1a Haplogroup has existed in India beyond 30,000 years as per Sharma et al. (2009). R1a1a existed since 8,000 to 10,000 years and this Haplogroup is extensively diversified all across India. If a group is extensively diversified, it is an indication that they have been in our land for a very long period. R1a1a has also been found in Eastern Europe, South & Central Asia & Middle East.
- The most common Y-DNA haplogroup in Europe is R1b, which is further divided into subclades like R1b1a1a2a1a2b (often abbreviated as R-M269). R1b genetic marker found in India is almost negligible. (<1%). Again, Neanderthal ancestry has been found in Europeans from 3 to 5% but it is almost negligible among Indians.
- 75% of the Indians speak Indo-European languages. 50-60% of them carry R1a Haplogroup. One Migration in 1500 BCE could not have caused this huge impact in altering the population genetics. Dr. Niraj Rai, a leading Geneticist of India, is the Head of the Ancient DNA lab in India and will be coming out with his latest research paper soon and that should answer many more questions on this subject.
Research in the field of human population genetics is ongoing, and our understanding of haplogroups may evolve over time as new data becomes available. The “out of Africa” migration is a key component of the human evolutionary history and it has had a profound impact on the genetic and cultural diversity of the world’s populations. It is important to note that our understanding of these events continues to evolve as new archaeological discoveries and genetic research are conducted.
India is a diverse and genetically complex country with a wide range of haplogroups due to its long and varied history of population migrations and interactions. Genetic studies in India are ongoing, and researchers continue to explore the rich genetic diversity and historical migrations of the subcontinent. The prevalence of specific haplogroups can provide insights into the complex history and population movements of India. Also, due to the harsh and varied climatic conditions in India, it is difficult to get ancient DNA due to degradation.
References: Few Snippets from the Book “The Saraswati Civilisation” by Maj.Gen GD Bakshi.
It is the desire of every ethnic community to know about their origins. A short You Tube Video on the scientific analysis of the Aryan Invasion Theory (<click here) and the orgin of the Indians of this sub-continent is explained here by an Indian Geneticist – Niraj Rai in Hindi language.