Saturday, February 20, 2016

The I-M253 Y-Chromosome Haplogroup

Some years ago, I supplied a tissue sample to the Timen Stiddem Society.  The sample was analyzed to ascertain the haplogroup for the Y-chromosome.  Y-chromosomes are inherited only by males from their fathers; it is the sex-determining factor, males having one X-chromosome from the mothers and one Y-chromosome from the father.  Females, in contrast, have two X-chromosomes, one from the mother and the other from the father.

The Y-chromosome has relatively few transcribed genes.  One estimate holds that the human Y-chromosome as lost 1,393 of its original 1,438 genes.  As such, it hosts the highest rates of mutation, because deleterious effects are rare.  In addition, most of the chromosome cannot recombine with the X-chromosome.  This non-recombining region of the chromosome ('NRY') is sequenced in terms of single nucleotide polymorphisms to trace direct paternal lines.  There are 37 regions that can be differentiated by pattern of SNPs falls into a limited number of groups.

My sample grouped with the I-M253 haplogroup.  This group is described in the Wikipedia link:

In human genetics, Haplogroup I-M253 is a Y chromosome haplogroup which occurs at greatest frequency in Fenno-Scandia. The mutations identified with Haplogroup I-M253 (Y-DNA) are M253, M307, P30, and P40. These are known as single nucleotide polymorphisms (SNPs). It is a subclade of Haplogroup I. Before a reclassification in 2008,[2] the group was known as Haplogroup I1a.
The group displays a very clear frequency gradient, with a peak of approximately 40 percent among the populations of western Finland and more than 50 percent in the province of Satakunta,[3] and around 38 percent in Sweden as a whole, with a peak of 52 percent in Västra Götaland County in central Sweden.[4]
In the Timen Stidham project, the I-M253 group is the most frequent among those who have participated.  However, my genealogy research does not yet support this connection.

The origin of the I-M253 pattern has been estimated to have occurred 3,470 - 5,070 years ago.  Using 4,000 years as a round number and an average generation time of 25 years, one can estimate that this is 160 generations since 2,000 BCE.

Famous people in the I-M253 haplogroup include Birger Jarl, one of Sweden's greatest medieval statesman, Alexander Hamilton, Andrew Jackson, Leo Tolstoy, Calvin Coolidge, Warren Buffett, and Jimmy Buffett.

These relationships should be considered in the context of the calculated 160 generations since the haplogroup emerged.  Think of eight generations back, 200 years, the time of Alexander Hamilton.  We would go this number of generations back times 20 to arrive at a the original I-M253.  Clearly, the haplogroup has little relevance in accounting for anything in my own life history.  

Another context would be the distance to the human 'Adam'.  He and 'Eve' are estimated to have lived 200,000 to 300,000 years ago.  Using the 25 year generation time, there have been 8,000 - 12,000 generations since our species separated into its current configuration.  I believe there is a timeline showing the estimates of the start of each haplogroup, but I don't know them off hand.  Using the letters in order, 'I' would be number 9, perhaps indicating a haplogroup emerging every 20,000 years. This estimation tracks well with literature numbers.  Put into another perspective, the origin of the I-M253 haplogroup occurred around the time of the separation of the Jewish and the Arab tribes.  Call me Ishmael!




8 comments:

  1. so, I-M253 is Arab, according to the Bible, it is like a wild donkey and other negatives.

    ReplyDelete
    Replies
    1. Maybe. Then again, 20,000 years or so is a blink of an eye

      Delete
  2. I got I-M253 from my father, whose father was a short dark eyed and hair German/French and his mother blue eyed Polish type. 23/me did say that I had Neanderthal variants,326. This is more than 98% of 23andMe Customers. "You have 1 Neanderthal variant associated with your height, You have 1 Neanderthal variant associated with a reduced tendency to sneeze after eating dark chocolate". On my mother's side, it is a rare(one out of 1000) J1cla, recent mutant of 3-10k years ago. So I have a little bit of the old, Neanderthal, and the recent evolutionary of J1c1a.

    ReplyDelete
  3. Hi .. I live in Saudi Arabia and fundamentalist from Yemen, but I was surprised by the result of a DNA test where the result was I-M253 and that means that I am a non-Arab fundamentalist but European assets ... Is this possible and does the result of the examination logical?

    ReplyDelete
    Replies
    1. This comment has been removed by the author.

      Delete
    2. if your ancestors came from Europe and converted to Islam, or were brought to Saudi Arabia as slaves why not? Many Bosniaks and Albans served in Egypt under Ottoman rule. Why the same couldn't happen is Saudi Arabia?

      Delete
    3. Barbary slave trade https://en.wikipedia.org/wiki/Barbary_slave_trade

      Don't be embarrassed, everybody was doing it. "Kinder, Gentler Vikings? Not According to Their Slaves
      New clues suggest slaves were vital to the Viking way of life—and argue against attempts to soften the raiders’ brutish reputation." https://news.nationalgeographic.com/2015/12/151228-vikings-slaves-thralls-norse-scandinavia-archaeology/

      Delete
  4. My brother got the I-M253 haplogroup and we are African-American. Less than 2% of his DNA was Neanderthal. Out of the 2,872 variants tested, 53 variants trace back to the Neanderthals.

    ReplyDelete