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DMXX
06-02-2014, 04:52 PM
From Dienekes' entry (http://dienekes.blogspot.co.uk/2014/06/a-molecular-basis-for-classic-blond.html). I would've posted this in the New DNA Papers (http://www.anthrogenica.com/showthread.php?709-New-DNA-Papers) thread, but the SNP highlighted here can be found in 23andMe's chips.

Please note that, on 23andMe, the ancestral (non-blonde) allele will be T and derived (blonde) C.

One curious find is the slight increase in derived/blonde alleles in one part of Southeast Asia relative to the rest, at a level consistent with the African Horn. Could this be attributed to the Hmong (http://s16.postimg.org/55pdeswyt/Blond_Asia6.jpg)?

Nevertheless, as the authors state, hair colour is a polygenetic trait and this appears to be a significant, but not definitive gene, for the blonde hair phenotype among Europeans specifically.

A molecular basis for classic blond hair color in Europeans
Catherine A Guenther et al.; Nature Genetics (2014) doi:10.1038/ng.2991


Hair color differences are among the most obvious examples of phenotypic variation in humans. Although genome-wide association studies (GWAS) have implicated multiple loci in human pigment variation, the causative base-pair changes are still largely unknown1. Here we dissect a regulatory region of the KITLG gene (encoding KIT ligand) that is significantly associated with common blond hair color in northern Europeans2. Functional tests demonstrate that the region contains a regulatory enhancer that drives expression in developing hair follicles. This enhancer contains a common SNP (rs12821256) that alters a binding site for the lymphoid enhancer-binding factor 1 (LEF1) transcription factor, reducing LEF1 responsiveness and enhancer activity in cultured human keratinocytes. Mice carrying ancestral or derived variants of the human KITLG enhancer exhibit significant differences in hair pigmentation, confirming that altered regulation of an essential growth factor contributes to the classic blond hair phenotype found in northern Europeans.



http://i61.tinypic.com/2h6hyk6.png

Mehrdad
06-02-2014, 05:01 PM
Makes me wonder if the blond gene from the Hmong made its way into the Melanesian population. Or could it be that the blond gene developed independently? 1929

DMXX
06-02-2014, 05:08 PM
I recall the Melanesian gene for blonde hair reportedly differs from those found in West Eurasians. It'd be interesting to see whether this mutation has any connection with the Melanesian people.

MikeWhalen
06-02-2014, 08:33 PM
I got lots of great pictures of blondes, if you need any :)

Mike

thetick
06-03-2014, 02:51 AM
I got lots of great pictures of blondes, if you need any :)


Does the carpet match the drapes? :)

Táltos
06-03-2014, 02:54 AM
Does the carpet match the drapes? :)
Probably not!

ViktorL1
06-03-2014, 03:09 AM
It's interesting that the G allele exists in Mongolia. I wonder what the prevalence would be among Mongolian Kazakhs vs ethnic Mongols..

venustas
06-03-2014, 03:25 AM
@Mehrdad The Melanesians have MP y-dna just like the Europeans. These Melanesians are not related to the Hmong.

venustas
06-03-2014, 03:26 AM
How come blond Siberians don't exist, And to be honest that gene looks like it is associated with U5 mtdna.

MikeWhalen
06-03-2014, 11:26 AM
carpet? what carpet?

:)

M


Does the carpet match the drapes? :)

alan
06-03-2014, 03:59 PM
Carpets have gone out of fashion and a well sanded subfloor is now all the rage among the young'uns by all accounts


carpet? what carpet?

:)

M

evon
06-03-2014, 04:34 PM
It's interesting that the G allele exists in Mongolia. I wonder what the prevalence would be among Mongolian Kazakhs vs ethnic Mongols..

Mongolia have had immigration from Europe as well as Central Asia since at least 500CE on-wards that i am aware of, likely earlier also..So it might be the source..

Chad Rohlfsen
06-03-2014, 07:12 PM
Mongolia have had immigration from Europe as well as Central Asia since at least 500CE on-wards that i am aware of, likely earlier also..So it might be the source..

More like 3300 BCE with the Afanesevo, possibly the ancestors of Tocharians.

DMXX
06-03-2014, 08:48 PM
More like 3300 BCE with the Afanesevo, possibly the ancestors of Tocharians.

I entertained this idea initially, but then noted the greater frequency of this derived allele in populations further north of Mongolians. I'm presuming the one directly above are the Yakut/Sakha people. The distance between the Mongolian plains and that part of Siberia looks roughly equidistant from Afanasievo. We can't cite additional East Eurasian admixture as having a "diluting" effect on the Mongolian genepool either given this equidistance, which would be the only rationalisation of that scenario, as the Sakha have their own history of intermingling extensively with non-Turkic, non-Indo-European natives in the region. That mixing's abundantly seen in their language.

To me at least, it looks like a two-way gradient exists; a strong one going from north to south, and a slightly weaker one from west to east. I like the idea of linking mtDNA U5 with it, as the "strong gradient" matches the zone ("migration corridor") inhabited by prehistoric Eurasian hunter-gatherers.

evon
06-03-2014, 09:19 PM
More like 3300 BCE with the Afanesevo, possibly the ancestors of Tocharians.

Dont know much about that period, but there have been recorded early Sogdian settlements (Aprox 200-500CE) in the wider Mongolian region, and during the Pax-Mongolica there was settlement of Germans, Ossetians and others in Mongolia as specialized workers and soldiers.. So you have a wide range of possibilities of entry..

J Man
06-07-2014, 08:18 PM
I entertained this idea initially, but then noted the greater frequency of this derived allele in populations further north of Mongolians. I'm presuming the one directly above are the Yakut/Sakha people. The distance between the Mongolian plains and that part of Siberia looks roughly equidistant from Afanasievo. We can't cite additional East Eurasian admixture as having a "diluting" effect on the Mongolian genepool either given this equidistance, which would be the only rationalisation of that scenario, as the Sakha have their own history of intermingling extensively with non-Turkic, non-Indo-European natives in the region. That mixing's abundantly seen in their language.

To me at least, it looks like a two-way gradient exists; a strong one going from north to south, and a slightly weaker one from west to east. I like the idea of linking mtDNA U5 with it, as the "strong gradient" matches the zone ("migration corridor") inhabited by prehistoric Eurasian hunter-gatherers.

Interestingly enough my mtDNA haplogroup is U5 (U5b2c2) and both my mother and I have CT at rs12821256 according to 23andme with all of my other family members who have tested having TT at this SNP. My mother is of 100% Irish/British Isles ancestry as far as we know. The thing is though that my mother ended up with medium brown hair after puberty and I have ended up with very dark brown hair but we were both blonde as young children. Maybe you have to be homozygous for the G/C allele at this SNP to have blonde hair I am not really sure. Now I know that the Mesolithic hunter-gatherers from Europe who have been tested for pigmentation SNPs so far have mainly turned out to be dark haired but maybe some light haired ones will be found in the future. We will have to wait and see.

parasar
06-08-2014, 04:33 PM
Papuans

When you ask the people why there are so many blonde people on the islands, they answer 3 things: they have white ancestors, they receive too much sun, or they do not eat enough vitamins!
http://www.flickr.com/photos/mytripsmypics/4022636212/
http://37.media.tumblr.com/tumblr_luzui9T67h1qfb8i2o1_500.jpg


The desert aborigines look like primitive Caucasians, with light skin and wavy or straight hair that can be blond. (Fig. 27-4; also Figure 22-5). 7 No, the children’s hair was not dyed blond. Amazing as it seems, some desert aborigines really do have straight or wavy, naturally blond hair. (Note 17 in Chapter 10)
http://erectuswalksamongst.us/Chap27.html
http://erectuswalksamongst.us/Images/Figure%2027-4.GIF

rms2
06-09-2014, 11:35 PM
Apparently Family Finder did not include rs12821256, because I cannot find a result for that among my raw data. Evidently rs1805005 is also associated with light blond hair. I have GG at that one, and the risk allele there is T: two Ts for blond hair, since the trait is recessive. I am not even a carrier for that one.

My maternal grandmother had long, thick, naturally blond hair, which stayed golden blond, with very little gray in old age, for her entire life, and she passed away at age 81.

Salkin
09-02-2014, 05:16 PM
A data point to stir the pot: I am rs12821256 TT. In spite of this, I was blond (fairly light) as a kid, but since puberty I have medium brown hair.

Promethease does list another blond marker in me, though, and one I can't tell which way it's supposed to go (I have greenish eyes post-puberty):


rs1667394(A;A)
Magnitude: 2.1
Frequency: 72.1%
References:8
blond hair & blue eyes is 4x more likely
...more...
(hide)
rs1667394 increases susceptibility to Blond rather than brown hair 4.94 times for carriers of the A allele rs1667394 increases susceptibility to Blue rather than brown eyes 29.43 times for carriers of the A allele rs1667394 increases susceptibility to Blue rather than green eyes 6.74 times for carriers of the A allele For green versus blue eye color rs12913832 in OCA2/HERC2 has a score of 51.5 and an estimated allelic OR of 8.43 . The SNP rs1667394 in this same region has an estimated OR of (4.85–10.06). [OMIM:HECT DOMAIN AND RCC1-LIKE DOMAIN 2; HERC2] [GWAS:Eye color]


rs4904868(T;T)
Frequency: 8.8%
References:2
...more...
(hide)
Web-based, participant-driven studies yield novel genetic associations for common traits. [PharmGKB:Non-Curated GWAS Results: Genetic determinants of hair, eye and skin pigmentation in Europeans (Initial Sample Size: 2,986 individuals; Replication Sample Size: 3,932 individuals). This variant is associated with blond vs. brown hair and blue vs. green eyes.] [GWAS:Blue vs. green eyes]

vettor
09-02-2014, 07:05 PM
A data point to stir the pot: I am rs12821256 TT. In spite of this, I was blond (fairly light) as a kid, but since puberty I have medium brown hair.

Promethease does list another blond marker in me, though, and one I can't tell which way it's supposed to go (I have greenish eyes post-puberty):


rs1667394(A;A)
Magnitude: 2.1
Frequency: 72.1%
References:8
blond hair & blue eyes is 4x more likely
...more...
(hide)
rs1667394 increases susceptibility to Blond rather than brown hair 4.94 times for carriers of the A allele rs1667394 increases susceptibility to Blue rather than brown eyes 29.43 times for carriers of the A allele rs1667394 increases susceptibility to Blue rather than green eyes 6.74 times for carriers of the A allele For green versus blue eye color rs12913832 in OCA2/HERC2 has a score of 51.5 and an estimated allelic OR of 8.43 . The SNP rs1667394 in this same region has an estimated OR of (4.85–10.06). [OMIM:HECT DOMAIN AND RCC1-LIKE DOMAIN 2; HERC2] [GWAS:Eye color]


rs4904868(T;T)
Frequency: 8.8%
References:2
...more...
(hide)
Web-based, participant-driven studies yield novel genetic associations for common traits. [PharmGKB:Non-Curated GWAS Results: Genetic determinants of hair, eye and skin pigmentation in Europeans (Initial Sample Size: 2,986 individuals; Replication Sample Size: 3,932 individuals). This variant is associated with blond vs. brown hair and blue vs. green eyes.] [GWAS:Blue vs. green eyes]

very strange we have nearly exact same traits..........I am similar to you as above. born blonde, changes to brown by early teens.

my paternal line is black hair and green eyes

you do not have a relation with this below......which is part of my maternal side
Hokansdotter; b.1630; Ljungby Sweden

BTW, I know dotter means daughter, so I have looked also for just Hokan

Salkin
09-03-2014, 02:34 AM
very strange we have nearly exact same traits..........I am similar to you as above. born blonde, changes to brown by early teens.

my paternal line is black hair and green eyes

you do not have a relation with this below......which is part of my maternal side
Hokansdotter; b.1630; Ljungby Sweden

BTW, I know dotter means daughter, so I have looked also for just Hokan

It is interesting, hard to say if it's a relation or just happenstance. I don't know much about my family history back to the 1600s, unfortunately... I could see about sharing some information from my mother, who's been doing a bit of genealogy. I'm not sure how far back she's reached.

-dotter and -son names are originally from the Scandinavian custom of patronymics, indeed, so that's "daughter of Håkan/Hokan", but that mostly stopped being done the traditional way with the introduction of Christianity; people just started using them as last names, like my -son name has nothing to do with my father's first name. By the 1600s the name might have been inherited unchanged for a number of generations.

Håkan is a fairly common first name, so I think searching on that might be difficult.

We could always look for common genes as a first step. If you have gedmatch my kit # is in my signature.

Tomenable
12-12-2015, 10:44 PM
There is a website SNPedia, with a search engine available:

http://snpedia.com/index.php?title=Special%3ASearch&profile=default&search=blond&fulltext=Search

Type "blond" and we find that there are over a dozen, around twenty, mutations associated with blond hair.

As for Melanesian blond hair: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3481182/#SD1

SwampThing27
12-12-2015, 10:57 PM
Whenever rs12821256 comes up in a discussion I like to post a picture of my hair. I'm actually CT for rs12821256 and heterozygous on most of the "blonde hair" snps. Enough that hirisplex predicts I have blonde hair at over 90%.