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kamani
19-11-13, 20:27
If "A" is the parent clade of all haplogroups and has been around longer, shouldn't it have the most members? Why isn't "A" the most common haplogroup on earth?

LeBrok
19-11-13, 20:56
If "A" is the parent clade of all haplogroups and has been around longer, shouldn't it have the most members? Why isn't "A" the most common haplogroup on earth?
Because their descendants, of mutated/new haplogroups were more genetically evolved for life in new geographic regions or new way of life of neolithic. They were more adapted to new environments, therefore they've overpopulated old HGs very quickly. Think natural selection.
For the same reason we don't have Neanderthals or other homo erectus anymore. We, the new breed of younger haplogroups, are more efficient in finding or producing food, making tools, and adapting to any climatic condition.

kamani
19-11-13, 21:46
Because their descendants, of mutated/new haplogroups were more genetically evolved for life in new geographic regions or new way of life of neolithic. They were more adapted to new environments, therefore they've overpopulated old HGs very quickly. Think natural selection.
For the same reason we don't have Neanderthals or other homo erectus anymore. We, the new breed of younger haplogroups, are more efficient in finding or producing food, making tools, and adapting to any climatic condition.

So this would mean that y-dna actually holds physical or behavioral traits that give an individual the evolutionary advantage.
It would also mean that people with haplogroup A are genetically disadvantaged in Europe, lets say.
I'm not fully convinced this is the answer because there are cases when between parent and child clade there are less than 5000 years difference, but the parent is nowhere to be found on earth and the child is very populous. Interesting point of view thou.

Sile
19-11-13, 22:01
If "A" is the parent clade of all haplogroups and has been around longer, shouldn't it have the most members? Why isn't "A" the most common haplogroup on earth?

If man did not move from where A commenced then the A marker would be much higher ( world population would be lower though)

geographic location of new settlements creates mutations.

Aberdeen
19-11-13, 22:10
If John Smith has five children, the first two children have one child each, the third and fourth children have no children because one is infertile and the other dies young, and the fifth child has ten children, the descendants of the fifth child would likely become more numerous in the long run. Although the same random differences of population frequency will appear in later generations, which could alter the percentages for the descendants of child one, two and five but not for the descendants of children three or four, since there are none. Also, as LeBrok said, mutations affect survival, and although mutations may not be tied to DNA, they may be associated with a particular haplotype if it becomes isolated for a period of time.

kamani
19-11-13, 22:26
lets say a tribe of hg A has 5000 males, one of them gets exposed to radiation and his hg become A1. Now the percentage of A1 in the tribe is 1/5000. Now the tribe moved from Africa to Europe. It is very obscure to me how did this percentage turned to 90% or even 50%, in the course of 4000 years, lets say.

Sile
19-11-13, 22:31
lets say a tribe of hg A has 5000 males, one of them gets exposed to radiation and his hg become A1. Now the percentage of A1 in the tribe is 1/5000. Now the tribe moved from Africa to Europe. It is very obscure to me how did this percentage turned to 90% or even 50%, in the course of 4000 years, lets say.

The numbers of A was less, so once some migrated, say 100 kms further away ,as an example mutations could have occurred, then they move again and another mutation etc

I would like to know if one tested 30 years ago and tested again now, would any new mutation occur.

LeBrok
19-11-13, 22:57
If man did not move from where A commenced then the A marker would be much higher ( world population would be lower though)

geographic location of new settlements creates mutations.

Mutations happen everywhere all the time, although they might happen more often when a tribe is in contact with uranium ore (the warm magic rocks) or when water is high in arsenic, or close supernova exploded. What really matters is when mutation already is in place and it turns to be beneficial for the carrier and its offspring. It's called adaptation. It is totally a blind process, and only lucky ones adapt by accident.


I would like to know if one tested 30 years ago and tested again now, would any new mutation occur. Absolutely they do, and happen all the time during cell divisions. However they are most important when they happen during early cell divisions or in egg and sperm cells before creation of new life, therefore one cell mutation can affect the whole new body.

Age of parents also have big influence on new mutations. The older we get the more mutations happen in our DNA, especially in sperm. Older parents have higher chance of conceiving unhealthy children. Because most of mutations are not good and make our bodies not function well.

matbir
20-11-13, 01:04
If "A" is the parent clade of all haplogroups and has been around longer, shouldn't it have the most members? Why isn't "A" the most common haplogroup on earth?
A is the most common haplogroup in the world, especialy A1b, because BT is its subclade. ;) It means that more than 99% of world male population belongs to subclades of A1b.
Y DNA haplogroup tree (http://www.isogg.org/tree/ISOGG_HapgrpA.html)

adamo
20-11-13, 02:25
Some of the stuff posted right here is total nonsense. The mutations are caused by uranium what exposure?

LeBrok
20-11-13, 03:33
Some of the stuff posted right here is total nonsense. The mutations are caused by uranium what exposure?
You can learn first hand, buy one online. We'll check for your mutations in 30 years. ;)
http://www.minresco.com/radioactive/radioactive01.htm

http://www.minresco.com/radioactive/ra_images/1974.JPG

adamo
20-11-13, 03:36
Yes and hopefully it will kill me if all turns as I hope haha, : )

LeBrok
20-11-13, 07:30
A is the most common haplogroup in the world, especialy A1b, because BT is its subclade. ;) It means that more than 99% of world male population belongs to subclades of A1b.
Y DNA haplogroup tree (http://www.isogg.org/tree/ISOGG_HapgrpA.html)
That's another way to look at this. Good point.

adamo
20-11-13, 09:34
Well the uranium didn't kill me but the booze and "other stuff" nearly did.

james stock
20-11-13, 17:07
Because population growth in the last millennium made all prior frequencies obsolete.

If you go back far enough the frequency of A would be highest because proto A would have been the only haplogroup.

I don't understand why you would think haplogroup A should have the highest frequency. Your question makes no sense.

http://cc.owu.edu/~rdfusch/long_term_growth.JPG

LeBrok
20-11-13, 18:28
Because population growth in the last millennium made all prior frequencies obsolete.

If you go back far enough the frequency of A would be highest because proto A would have been the only haplogroup.

I don't understand why you would think haplogroup A should have the highest frequency. Your question makes no sense.


Well, sometimes it is just a pure luck involved. For example, if hg A was very popular in England 500 years ago, then by means of industrial revolution, population explosion and GB imperialism, this hg would have been dominant in US, Canada and Australia, and also spread around the whole world.

We also have to remember that tribes of the past went through many bottlenecking till pretty much Neolithic. This surely made many hg obsolete, partly by luck and partly by natural selection, because less adapted to certain environment die first.

kamani
20-11-13, 19:58
I don't understand why you would think haplogroup A should have the highest frequency. Your question makes no sense.


I don't think A should have the highest frequency, I'm just trying to picture how do parent haplogroups disappear. Like R1* for example, there is only a few samples in the world found. It's frequency went to 0.000001% in just 30k years.

Aberdeen
23-11-13, 01:32
I don't think A should have the highest frequency, I'm just trying to picture how do parent haplogroups disappear. Like R1* for example, there is only a few samples in the world found. It's frequency went to 0.000001% in just 30k years.

It appears that most of the R1* people mutated into R1a or R1b, which are two very common haplotypes today. And I imagine that A is now rare because most A folk mutated into something else. The bottlenecks that LeBrok mentioned are important for determining whether a particular haplotype flourishes or dies back, but has been explained, the haplotypes often mutate into different haplotypes. I don't know what's difficult to understand about that. After 50,000 years, there aren't many people left with no mutations away from A.

kamani
23-11-13, 03:09
It appears that most of the R1* people mutated into R1a or R1b, which are two very common haplotypes today.
I believe that is incorrect. Out of all the R1* people only one of them mutated into R1a and one into R1b. Out of those 2 people come all the R1a and R1b today. R1* was born 25700 years BP and R1b/R1a were born 18500 BP. So I guess the R1 population was fairly small and over 7000 years a lot of mutations happened. And then probably there was a severe bottleneck that wiped out all the R1* and any other child mutations of it except R1a/R1b. I don't know..., that's my scenario.

MOESAN
23-11-13, 14:41
it is statistical all the way, linked to number and passing time- I'm trying to explain that like this
I think in a regularly growing population, some mutations occurred that diminish the previous weight of the basic form of HG - as time pass we can suppose (except in small population) the previous basic (no more mutated forms tend to decrease and finally to disappear,being the first place given to the first step mutation before this one suffers the same process - it would be a slow process but it is inevitable (I do'nt speak here about rare but possible back mutations)
the names given to Hgs are arbitrary because all the B, C, E... Q, R... Hg's are in fact subgroups of A, if I have well understood
so me 5R1bL21) is in fact a kind of "Y-A3c1b12h2a5....................................... ....." the oldest the form the most chances to decrease after thousands and thousands of generations, it 's dynamics - we are all from the same stock, but others names were given to new branches
it is theorical here because demography is not regular, there have been bottlenecks, founder effetcs... just a try to explainmy point - am i wrong?