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Angela
15-02-17, 19:11
This paper includes the snps responsible as well as predictive percentages.

See:

http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006594

Hagenaars et al:

Genetic prediction of male pattern baldness
"Male pattern baldness can have substantial psychosocial effects, and it has been phenotypically linked to adverse health outcomes such as prostate cancer and cardiovascular disease. We explored the genetic architecture of the trait using data from over 52,000 male participants of UK Biobank, aged 40–69 years. We identified over 250 independent genetic loci associated with severe hair loss (P<5x10-8). By splitting the cohort into a discovery sample of 40,000 and target sample of 12,000, we developed a prediction algorithm based entirely on common genetic variants that discriminated (AUC = 0.78, sensitivity = 0.74, specificity = 0.69, PPV = 59%, NPV = 82%) those with no hair loss from those with severe hair loss. The results of this study might help identify those at greatest risk of hair loss, and also potential genetic targets for intervention.Author summaryLiving with male pattern baldness can be stressful and embarrassing. Previous studies have shown baldness to have a complex genetic architecture, with particularly strong signals on the X chromosome. However, these studies have been limited by small sample sizes. Here, we present the largest genome-wide study of baldness to date, using data from over 52,000 male participants in the UK Biobank study. We identify over 200 novel findings. We also split our dataset in two to build and apply a genetic predictor of baldness. Of those with a polygenic score below the median, 14% had severe hair loss and 39% no hair loss. By contrast, of those with a polygenic score in the top 10%, 58% reported moderate-to-severe hair loss."

This I didn't know...
"some, but not all, studies have identified negative health outcomes associated with baldness including increased risk of prostate cancer [4 (http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006594#pgen.1006594.ref004)–6 (http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006594#pgen.1006594.ref006)] and cardiovascular disease [7 (http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006594#pgen.1006594.ref007)–9 (http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006594#pgen.1006594.ref009)]."

I also had some misinformation in that in the popular press it said that it was passed down through the mother. First of all, although there's an association with the X chromosome, that X chromosome could come from the father's mother etc. Also, there are some autosomal snps involved. I suspected that popular reports were incorrect just through personal experience: my brother started balding in his late twenties, just like my father, whereas the men in my mother's family had a full head of hair into their sixties.

I do realize, as the study states, that many men have real problems with this. Perhaps because my father had some baldness and was still, in my opinion, very good looking, I've never associated it with lack of good looks. Maybe it depends on the face, I also quite like the shaved head look on certain men. Some very attractive "hair challenged" men:

Justin and Pierre Trudeau...the son obviously gets his good looks mainly from his father...
https://thestudio1english.files.wordpress.com/2012/09/justinpierretrudeauweb.jpg

The gorgeous Julio Iglesias:
https://images-na.ssl-images-amazon.com/images/I/71kHzp7amxL._SX355_.jpg

My favorite baldies:
http://images4.fanpop.com/image/photos/17900000/Yul-Brynner-and-Deborah-Kerr-The-Journey-yul-brynner-17921380-412-500.jpg

http://st.baskino.club/uploads/images/2015/779/bkos932.jpg

Yetos
15-02-17, 19:53
At 70's 80's baldness was in fashion
on cinema and TV

http://americanprofile.com/wp-content/uploads/2006/08/telly_savalas_gc.jpg



anyway,
at my area we 'believe' as a moto that bald people have more testorone,

bicicleur
15-02-17, 20:00
anyway,
at my area we 'believe' as a moto that bald people have more testorone,

there is 'good' and 'bad' testosterone, and the 'bad' testosterone creates baldness

baldness would not be related to the level of testosterone, but to testosterone level swings

and there are more stories like that .. pick yours

Angela
15-02-17, 20:24
there is 'good' and 'bad' testosterone, and the 'bad' testosterone creates baldness

baldness would not be related to the level of testosterone, but to testosterone level swings

and there are more stories like that .. pick yours

What's the difference between good and bad testosterone?

Maciamo
15-02-17, 22:20
there is 'good' and 'bad' testosterone, and the 'bad' testosterone creates baldness

baldness would not be related to the level of testosterone, but to testosterone level swings

and there are more stories like that .. pick yours


It's not so much good vs bad testosterone, but rather two forms of testosterone with different functions. Baldness, beard, body hair, muscles, aggressiveness, and other secondary male characteristics are caused by dihydrotestosterone (DHT) (https://en.wikipedia.org/wiki/Dihydrotestosterone). The same DHT is also responsible for acne, high sex drive, and increased risk of prostate cancer. Testosterone is converted into DHT by the the testes, prostate and skin. The amount converted may vary depending on one's genome, and there is a good chance that several of the SNPs listed in this study have an influence on that.

Angela
15-02-17, 23:54
Male Pattern Baldness percentages by country:
http://cdn-ak.f.st-hatena.com/images/fotolife/n/nbakki/20140523/20140523231908.jpg

Some more great looking baldies:
Jason Stratham
https://s-media-cache-ak0.pinimg.com/736x/44/63/3f/44633f9bdc78ecc8f82ad51925ccde4c.jpg

Andre Agassi:
https://s-media-cache-ak0.pinimg.com/originals/6a/16/ed/6a16ed4783b5d51125b53be40fb3ca29.jpg

Patrick Stewart
https://s-media-cache-ak0.pinimg.com/236x/b1/2a/5e/b12a5e677d915ccf22a7d059186b7251.jpg

Mark Strong
http://ethnicelebs.com/wp-content/uploads/2013/10/Mark-Strong.jpg

LeBrok
16-02-17, 00:06
Interesting. Europe owns it. A manifestation of R1 haplogroups? ;)

Sennevini
16-02-17, 11:34
Here are the main patterns:

https://media.licdn.com/mpr/mpr/shrinknp_800_800/AAEAAQAAAAAAAAaiAAAAJGE1MGYzZjRlLWQyYWItNDc5Ny1hNz AwLTI1N2U5OTQwMDEzOQ.png

I wonder how it will play out with my hair. I think it is 2 right now, in my mid-20s. My father's line follows the vertex pattern, stopping around 4/5;
my mother's line however, follows the anterior pattern up until 7. I think the next 10 years are crucial.

Angela
16-02-17, 17:20
Interesting. Europe owns it. A manifestation of R1 haplogroups? ;)

I'm not sure because I don't know how seriously to take that list. I would have thought Italy would have been higher on the rankings, for example. It's really unremarkable for men to go bald in Italy, nor have I ever noticed much angst about it, but then I'm not a man so maybe I'm wrong.

I wonder what the rates are in places like Turkey or other areas in the Middle East, if they were surveyed? Maybe it's just a West Eurasian thing. It's certainly not an East Asian thing, and my impression is that Africans don't go bald at really high rates.