My Genetic Journey

Not having the slightest idea about my lineage beyond my great-grandfather, I was clueless about my roots, and not wearing a Syed or Mughal hat did not help matters either. Whatever documentary records existed, were left behind in the mayhem of Partition in 1947, when my parents’ families migrated from Jalandhar in Indian Punjab. All that remained were stories, happily twisted by the bards and passed down the generations. Some years ago, I heard of DNA tests being used for genealogy, and given my high school studies in the pre-medical stream – albeit four decades ago – I could faintly figure out the basics. I quickly caught up with the latest in the field of ‘population genetics’ through two very useful books for the layperson: The Journey of Man by Spencer Wells and Seven Daughters of Eve by Bryan Sykes. The former explains the development and world-wide spread of male lineages while the latter discusses the female lineages in Europe. As I finished the books, I became sufficiently enthused to order DNA tests through the Internet. This entailed an inside-the-cheek scrape with sterilised cotton buds sent by the testing company; the cotton buds carrying the DNA sample were returned through courier. Six weeks later, as promised, I received the report with about as much anxiety as on a final exam result announcement!

My Patriline

My patriline (father, father’s father … and so on) was determined through what is known as a Y-Chromosome DNA test. The patriline was found to belong to Haplogroup (unique group) R2, one of several hundred male groups and sub-groups discovered so far.  The group originated in  northern Pakistan about 26,000 years ago when one of its members underwent a mutation (M-479) on his Y-Chromosome.  This mutation marked him as different from his Haplogroup R ancestors (‘R’ having originated 30,000 years ago). My DNA test revealed the presence of the Haplogroup R2 defining marker M-479, and the sub-clan R2a marker M-124. 

The timeframe as to when the defining mutation took place is determined by noting the number of markers present, each mutation occurring on an average every 5,000 years. With five mutation markers identified on my Y-DNA prior to M-479 (viz, M207, M45, M9, M89, and M168), the age of my Haplogroup R2 turns out to be 26,000 years.


The place of origin of the mutation can be determined by noting in which part of the world maximum variants of a particular haplogroup exist; this is because longer the haplogroup has been around, more time for varieties to crop up.  In case of R2, the maximum variation exists in the region of northern Pakistan and Tajikistan, implying that R2 people have existed for the longest period in that region.

R2 people eventually left the mountainous north, with nine out of every ten men gradually moving to the fertile Indus and Ganges river valleys of South Asia, where this group’s prevalence today stands at around 9% of the male population. In Pakistan, 7% of all males are of R2 lineage. An unusually high R2 spike at 37% has been observed amongst the Burusho-speaking males from Hunza, albeit from a small sample population.  Haplogroup R2 is responsible for one of the three earliest large scale population dispersals into South Asia, and the R2 people can vie for the title of ‘sons-of-the-soil’ along with those of Y-Chromosome Haplogroups H and L.

While 90% of individuals belonging to Haplogroup R2 are present in South Asia, the remainder are found in Central Asia, Anatolia, and the Caucasus.  Outside of South Asia, the frequency breakdown of Haplogroup R2 within their respective population groups is as follows: Kurds 10%, Tajiks 6%, Georgians 4%, Uyghurs 4%, Uzbeks 3%, Armenians 2%, Azerbaijanis 2%, Kazakhs 2%, Kyrgyz 2% and Turks 2%. A few population groups show a disproportionately high incidence of R2; these include Sinte Roma 53%, Bartangi Tajiks 17%, and Chechens 16%.

My Haplogroup R2 also conveys a lot more about my lineage in a roundabout way. It tells me that, were I to claim holy Arab lineage (with surnames like Abbasi, Ansari, Farooqui, Hashmi, Qureshi, Siddiqui, Syed, Usmani, etc) it would be bogus, because virtually all Arabs of the peninsula belong to the male Haplogroups J1 and J2, and some I and G. Similarly, any pretensions about my being an imperial Mongol (with surnames like Baig, Barlas, Changezi, Chughtai, Mirza, Mughal, etc) would be unfounded because Mongols belong to Haplogroup C2. So with no regal or sacred surname embellishing our family, it is likely that our paternal ancestors moved into South Asia, and settled down as simple farmers in the Indo-Gangetic plains; they could well be the precursors of the Harappans, I'd like to imagine.  The presence of R2 deep down in Sri Lanka, South India and Bangladesh points to these early migrations, which continued over a long timespan. Much later, the R2 men were joined by R1a pastoral nomads of the Central Asian steppes, who started to migrate around the time the Harappan Civilisation started to 'de-urbanise' around 1900 BC; today, R1a presence is more pronounced in Pakistan and Northern India.

It would be so much fun to retrace the route of prehistoric migrations of my R2 ancestors, but for the present there are no clear clues. If I were to join the dots between centres of present day R2 concentrations in South Central Asia, I would see myself travelling through  Dushanbe, Kabul, Hunza, and Peshawar, and then debouching onto the Punjab plains, terminating my journey at Jalandhar.

My Matriline

My matriline (mother, mother’s mother … and so on) was determined through what is known as a mitochondrial DNA test.  The matriline was found to belong to Haplogroup J, one of several hundred female groups and sub-groups discovered so far.  Haplogroup J originated 45,000 years ago when a mutation took place in the DNA of a woman who lived in the Anatolian-Caucasus region. The mutation left a tell-tale signature in her mitochondrial DNA that is carried by all of her female descendants to this day. Thus, all of them can be identified by the J ‘badge’.

Further mutations took place on the J line, which can be identified as J1a1 (27,000 years ago), J2a (19,000 years ago), J2b2 (16,000 years ago), etc. Each of these mutations took place in the DNA of women who can be termed as the ‘first ladies’ of their sub-clans. Their identity endures almost as a bar code in the ‘J’ women of today. My maternal sub-clan is J2b2.

Haplogroup J is associated with the spread of farming and herding in Europe during the Neolithic Era (8,000-10,000 years ago). All other West Eurasian origin haplogroups were previously given to hunting and gathering.

mtDNA Haplogroup J2 Migration Map

Of the two main sub-groups, J1 takes up four-fifths of the total, and is spread mostly on the European continent. J1 is also found amongst Saudis, Yemenis, Iraqis and Palestinians. J2 is more localised around the Mediterranean, notably in Turkey, Greece, Italy/Sardinia and Spain. A surprising presence of J2 (10%) amongst the Mansi of Ob river valleys in Russia, indicates a Neolithic Phase expansion towards the Urals. East of the Caucasus, occurrence of J2 has been noted in Northern Iran at 5%, Azerbaijan at 3% and Turkmenistan at 3%.

In Pakistan, where West Eurasian lineages occur at frequencies of up to 50% in some ethno-linguistic groups, J1 averages around 5%, while J2 occurrence is very rare. Intriguingly, however, it is found amongst 9% of Kalash women.



It is also likely that some of my J2 ancestral women (along with their men, of course) migrated across the Caucasus on to the steppes north of Caspian and Black Seas, which was the heartland of R1a males. While R1a men are mostly found in East Europe, they also swung east and migrated into South Asia as the Vedic Aryans, starting around 2000 BC. My mother’s patriline of R1a attests to this occurrence. So that is how a few J2 women (along with their R1a men) ended their sojourn in what is now Pakistan. When and where a R2 man from my father’s side married the first ‘outsider’ J2 woman from my mother’s side will, perhaps, remain an enduring mystery.

My Ethnic Origins

The patriline and matriline tests look at a very specific and narrow segment of a person’s ancestry by testing for only Y-Chromosome and mtDNA respectively.  In each generation, only one person is of interest.  Five generations mean just five patrilineal or matrilineal ancestors (eg, father, grandfather, great grandfather, G-G-grandfather, G-G-G-grandfather). Thus, it can be seen that these two tests do not provide a comprehensive picture of one’s ethnicity, and are only meant to check for specific lineages.

The ethnic origins test looks at all 22 pairs of autosomal chromosomes. Thus, the complete genetic contribution of every generation is available. With every generation, the contributors double in number, so the genetic material for testing is vast. As an example, the fifth generation has 32 ancestors; tenth generation would have 1,024 ancestors! Theoretically speaking, tests are not limited by how far back can testing be done, so one can actually check for one’s Neanderthal great-great-great grand uncles and aunties as well!

I took an ethnic origins test to determine my ethnic composition. The results were a little surprising, but when looked at in light of my patrilineal and matrilineal origins, things did fall in place.

I am 77% South Asian, 13% West Asian, 6% Central Asian, 2% Irish-Scottish-Welsh and 2% Balkan. My patrilineal and matrilineal results provide clear clues in understanding these ethnic origins. The first three ethnicities are quite easy to figure out as my father’s side moved to South Asia from Central Asia, and my mother’s side moved to South Asia from West Asia (Anatolia and Caucasus region).  The latter two ethnicities reflect those West Asian cousins who migrated west, and ended up in Northern and Southern Europe instead of turning east for South Asia. In other words, we all shared a common ancestor a few millennia ago.

The ethnic origins results can be uploaded to third party ancestry sites for free, and allow a ‘second opinion’ on the raw results. I have done that, and generally, the ethnic origins are quite in agreement. Slight variations are there because different testing companies follow different testing protocols, and also, the interpretation of various geographical areas like Central Asia and West Asia is different.

The only challenge that remains for me is to discover definite migration routes followed by my ancestors into South Asia from their far-off places of origins in West Asia and Central Asia. As the data base of tested population groups expands, joining the dots is bound to become more precise. Once that happens, I would have truly come home!

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GLOSSARY OF TERMS

Chromosome – Structure found in the nucleus of a cell, which contain the genes. Humans have 23 pairs of chromosomes (22 pairs of autosomes and two sex chromosomes).

DNA (DeoxyriboNucleic Acid) – Known as the structure of heredity, the DNA is a chemical consisting of a sequence of hundreds of millions of nucleotides found in the nucleus of cells and that contains the genetic information about an individual; DNA is shaped like a double-stranded helix.
 
Gene – A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins. A complete set of genetic instructions is called a Genome.

Haplogroup – A haplogroup is a genetic population group of people who share a common ancestor on the patrline or matriline. Haplogroups are assigned letters of the alphabet, and sub-groups consist of additional number and letter combinations.

Mutation – An inheritable change that may occur in a gene or in a chromosome, and may take the form of a chemical rearrangement, or a partial loss or gain of genetic material.

Mitochondrial DNA (mtDNA) – It is the DNA located in cellular mitochondria that convert chemical energy from food into a form that cells can use. mtDNA is inherited solely from the mother. mtDNA is a powerful tool for tracking ancestry through females, and has been used in this role to track the ancestry back hundreds of generations.

Nucleotides – These are the alphabets of DNA. There are four of them: adenine (A), thymine (T), guanine (G) and cytosine (C). They always go by pairs, A with T, and G with C. Such pairs are called "base pairs". The 46 chromosomes of human DNA are composed of a total of 3 billion base pairs. The Y-chromosome possesses 60 million base pairs, against 153 million for the X chromosome.  mtDNA consists of only 16,569 base pairs.

Y chromosome – One of the two sex chromosomes, X and Y. The Y chromosome passes down from father to son. Females do not receive it. Since the Y chromosome goes down the paternal line, it is valuable for genealogy studies, since in general it follows a surname line.