Category: Genetics
-
How did modern humans settle the world?
In lieu of lots of text, above is a stylized representation of the routes which Neo-Africans took ~50 thousand years ago from their point of departure to parts unknown. The two colors represent two models. The red lines show two major streams issuing …
-
On the genetic structure of Afro-Indians
The Pith: Afro-Indians are mostly African, with a substantial Indian minority ancestry. The latter is disproportionately female mediated. It also seems that that ancestry is more northwest Indian, and that natural selection has been operating upon them…
-
Everything I didn’t know about sex
The Pith: The primary reason for the pervasiveness of sex among complex organisms is to maintain genomic integrity, not to increase genetic variation.. I just read a very strange article in the journal Evolution, Sex reduces genetic variation. In it th…
-
The biocultural frog and tortoise
As many of you know when you have two adjacent demes, breeding populations, they often rapidly equilibrate in gene frequencies if they were originally distinct. There are plenty of good concrete examples of this. The Hui of China are Muslims who speak…
-
Marry far and breed tall strong sons
The Pith: When it comes to the final outcome of a largely biologically specified trait like human height it looks as if it isn’t just the genes your parents give you that matters. Rather, the relationship of their genes also counts. The more diss…
-
Tightening the interval of the expected
The Pith: The rarer the genetic variant, the more likely that variant is to be specific to a distinct population. Including information about the distribution of these genetic variants missed in current techniques can increase greatly the precision of …
-
Disease and human demographic history
There’s a write-up in The New York Times on a new paper to come out in PNAS soon on the relationship of disease variants to human demographic history over the past few hundred thousand years. I’ll probably review the paper when it comes ou…
-
Any Tutsi genotypes around?
If anyone has, or knows of, Tutsi genotypes that I could analyze for the African Ancestry Project, could you please email me at africanancestryproject-at-gmail-dot-com? I want to ascertain the extent of genetic differences between Tutsi and Bantu popul…
-
Pakistani genome
Scientists map genome of first Pakistani man: “Our nation is a mix of a lot of races,” said Prof. Dr M Iqbal Choudhary, who heads the project. “Pakistanis are like a “melting pot” ie a mix of Mughals, Turks, Pashtuns, Afghans, Arabs, etcetera…
-
“What if you’re wrong” – haplogroup J
Back when this sort of thing was cutting edge mtDNA haplogroup J was a pretty big deal. This was the haplogroup often associated with the demic diffusion of Middle Eastern farmers into Europe. This was the “Jasmine” clade in Seven Daughters…
-
South Asian genetics would be nowhere without Pakistan
It looks like there have been some changes in the South Asian samples in the 1000 Genomes Project. Earlier there had been a notification that they were trying to get obtain samples of Kayasthas from West Bengal, Marathas from Maharashtra, and Ahom from Assom. No more. Now you have Sri Lankan and Bangladesh populations. What…
-
Reify my genes!
BEHOLD, REIFICATION! In the comments below Antonio pointed me to this working paper, What Do DNA Ancestry Tests Reveal About Americans’ Identity? Examining Public Opinion on Race and Genomics. I am perhaps being a bit dull but I can’t figure …
-
First Farmers Facing the Ocean
The image above is adapted from the 2010 paper A Predominantly Neolithic Origin for European Paternal Lineages, and it shows the frequencies of Y chromosomal haplogroup R1b1b2 across Europe. As you can see as you approach the Atlantic the frequency co…
-
Heritability and genomics of facial characteristics
On several occasions I’ve gotten into discussions with geneticists about the possibility of reconstructing someone’s facial structure by genes alone. Combined with advances in pigmentation prediction by genetics, this could put the sketch a…
-
The different dynamics of memes vs. genes
In my long post below, Celts to Anglo-Saxons, in light of updated assumptions, I had a “cartoon” demographic model in mind which I attempted to sketch out in words. But sometimes prose isn’t the best in terms of precision, and almost …
-
Every South Asian “Arab” a descendant of Muhammad!
Y chromosomes of self-identified Syeds from the Indian subcontinent show evidence of elevated Arab ancestry but not of a recent common patrilineal origin: Several cultural or religious groups claim descent from a common ancestor. The extent to which this claimed ancestry is real or socially constructed can be assessed by means of genetic studies. Syed…
-
Hints of Ötzi’s genome
John Hawks points to a report in Science on some morsels of information about Ötzi-the-Iceman’s genetics, The Iceman’s Last Meal: Also at the meeting, researchers led by geneticist Angela Graefen of the Institute for Mummies and the Icema…
-
Breaking the “Central Dogma”
Epigenetics is making it “big time,” Slate has a review up of the new book Epigenetics: The Ultimate Mystery of Inheritance. In case you don’t know epigenetics in terms of “what it means/why it matters” holds out the promi…