I am rereading Sam Kean’s book “The Violinist’s Thumb”, which is pop-sci genetics. From the book:

“In 2005 scientists reported that two mutated brain genes seem to have swept torrentially through our ancestors microcephalin doing so 37,000 years ago and aspm just 6,000 years ago”

Now, I’ve found a paper that says Australian Aboriginal people have some Neandertal and some Denisovan traces but they were well and truly here in Australia 37,000 and 6,000 years ago. I wonder if these brain genes (apparently they have something to do with brain size) are in their genome. Puts a bit of a spanner in the works if they are. Interesting if they are not. I haven’t yet found any research on it.

buffy said:

I am rereading Sam Kean’s book “The Violinist’s Thumb”, which is pop-sci genetics. From the book:

“In 2005 scientists reported that two mutated brain genes seem to have swept torrentially through our ancestors microcephalin doing so 37,000 years ago and aspm just 6,000 years ago”

Now, I’ve found a paper that says Australian Aboriginal people have some Neandertal and some Denisovan traces but they were well and truly here in Australia 37,000 and 6,000 years ago. I wonder if these brain genes (apparently they have something to do with brain size) are in their genome. Puts a bit of a spanner in the works if they are. Interesting if they are not. I haven’t yet found any research on it.

These mutations are from Neandertal and Denisovan ?

Cymek said:

buffy said:

I am rereading Sam Kean’s book “The Violinist’s Thumb”, which is pop-sci genetics. From the book:

“In 2005 scientists reported that two mutated brain genes seem to have swept torrentially through our ancestors microcephalin doing so 37,000 years ago and aspm just 6,000 years ago”

Now, I’ve found a paper that says Australian Aboriginal people have some Neandertal and some Denisovan traces but they were well and truly here in Australia 37,000 and 6,000 years ago. I wonder if these brain genes (apparently they have something to do with brain size) are in their genome. Puts a bit of a spanner in the works if they are. Interesting if they are not. I haven’t yet found any research on it.

These mutations are from Neandertal and Denisovan ?

No, much later.

buffy said:

I am rereading Sam Kean’s book “The Violinist’s Thumb”, which is pop-sci genetics. From the book:

“In 2005 scientists reported that two mutated brain genes seem to have swept torrentially through our ancestors microcephalin doing so 37,000 years ago and aspm just 6,000 years ago”

Now, I’ve found a paper that says Australian Aboriginal people have some Neandertal and some Denisovan traces but they were well and truly here in Australia 37,000 and 6,000 years ago. I wonder if these brain genes (apparently they have something to do with brain size) are in their genome. Puts a bit of a spanner in the works if they are. Interesting if they are not. I haven’t yet found any research on it.

I think I don’t quite get your point. Could you lay it out for me more plainly? I might be having a bad brain day.

From Wikipedia:

Controversy

The research results began to attract considerable controversy in the science world. John Derbyshire wrote that as a result of the findings, “our cherished national dream of a well-mixed and harmonious meritocracy may be unattainable.” Richard Lewontin considers the two published papers as “egregious examples of going well beyond the data to try to make a splash.” Bruce Lahn maintains that the science of the studies is sound, and freely admits that a direct link between these particular genes and either cognition or intelligence has not been clearly established. Lahn is now engaging himself with other areas of study. Later studies have not found those gene variants to be associated with mental ability or cognition.

Later genetic association studies by Mekel-Bobrov et al. and Evans et al. also reported that the genotype for MCPH1 was under positive selection. An analysis by Timpson et al., found “no meaningful associations with brain size and various cognitive measures”. A later 2010 study by Rimol et al. demonstrated a link between brain size and structure and two microcephaly genes, MCPH1 (only in females) and CDK5RAP2 (only in males). In contrast to previous studies, which only considered small numbers of exonic single nucleotide polymorphisms (SNPs) and did not investigate sex-specific effects, this study used microarray technology to genotype a range of SNPs associated with all four MCPH genes, including upstream and downstream regulatory elements, and allowed for separate effects for males and females.

https://en.wikipedia.org/wiki/Microcephalin

dv said:

buffy said:

I am rereading Sam Kean’s book “The Violinist’s Thumb”, which is pop-sci genetics. From the book:

“In 2005 scientists reported that two mutated brain genes seem to have swept torrentially through our ancestors microcephalin doing so 37,000 years ago and aspm just 6,000 years ago”

Now, I’ve found a paper that says Australian Aboriginal people have some Neandertal and some Denisovan traces but they were well and truly here in Australia 37,000 and 6,000 years ago. I wonder if these brain genes (apparently they have something to do with brain size) are in their genome. Puts a bit of a spanner in the works if they are. Interesting if they are not. I haven’t yet found any research on it.

I think I don’t quite get your point. Could you lay it out for me more plainly? I might be having a bad brain day.

Perhaps I wasn’t quite clear. The mention of Neandertal and Denisovan is probably irrelevent here. What I’m finding interesting is that the brain genes are said to have swept the human population later than the Aboriginal people came here, and before there was contact with the other humans from Asia, Europe etc.. They were rather isolated here for a very long time.

Bubblecar said:

From Wikipedia:

Controversy

The research results began to attract considerable controversy in the science world. John Derbyshire wrote that as a result of the findings, “our cherished national dream of a well-mixed and harmonious meritocracy may be unattainable.” Richard Lewontin considers the two published papers as “egregious examples of going well beyond the data to try to make a splash.” Bruce Lahn maintains that the science of the studies is sound, and freely admits that a direct link between these particular genes and either cognition or intelligence has not been clearly established. Lahn is now engaging himself with other areas of study. Later studies have not found those gene variants to be associated with mental ability or cognition.

Later genetic association studies by Mekel-Bobrov et al. and Evans et al. also reported that the genotype for MCPH1 was under positive selection. An analysis by Timpson et al., found “no meaningful associations with brain size and various cognitive measures”. A later 2010 study by Rimol et al. demonstrated a link between brain size and structure and two microcephaly genes, MCPH1 (only in females) and CDK5RAP2 (only in males). In contrast to previous studies, which only considered small numbers of exonic single nucleotide polymorphisms (SNPs) and did not investigate sex-specific effects, this study used microarray technology to genotype a range of SNPs associated with all four MCPH genes, including upstream and downstream regulatory elements, and allowed for separate effects for males and females.

https://en.wikipedia.org/wiki/Microcephalin

I knew it was debated what the genes were actually doing, but I’m more interested in the suggestion they swept through the whole population of humans well after the Australian Aboriginal people were isolated away here.

buffy said:

Bubblecar said:

From Wikipedia:

Controversy

The research results began to attract considerable controversy in the science world. John Derbyshire wrote that as a result of the findings, “our cherished national dream of a well-mixed and harmonious meritocracy may be unattainable.” Richard Lewontin considers the two published papers as “egregious examples of going well beyond the data to try to make a splash.” Bruce Lahn maintains that the science of the studies is sound, and freely admits that a direct link between these particular genes and either cognition or intelligence has not been clearly established. Lahn is now engaging himself with other areas of study. Later studies have not found those gene variants to be associated with mental ability or cognition.

Later genetic association studies by Mekel-Bobrov et al. and Evans et al. also reported that the genotype for MCPH1 was under positive selection. An analysis by Timpson et al., found “no meaningful associations with brain size and various cognitive measures”. A later 2010 study by Rimol et al. demonstrated a link between brain size and structure and two microcephaly genes, MCPH1 (only in females) and CDK5RAP2 (only in males). In contrast to previous studies, which only considered small numbers of exonic single nucleotide polymorphisms (SNPs) and did not investigate sex-specific effects, this study used microarray technology to genotype a range of SNPs associated with all four MCPH genes, including upstream and downstream regulatory elements, and allowed for separate effects for males and females.

https://en.wikipedia.org/wiki/Microcephalin

I knew it was debated what the genes were actually doing, but I’m more interested in the suggestion they swept through the whole population of humans well after the Australian Aboriginal people were isolated away here.

The Wiki article says:

A derived form of MCPH1 appeared about 37,000 years ago (any time between 14,000 and 60,000 years ago) and has spread to become the most common form of microcephalin throughout the world except Sub-Saharan Africa; this rapid spread suggests a selective sweep.

…but doesn’t mention Australian population of the time.

buffy said:

Bubblecar said:

From Wikipedia:

Controversy

The research results began to attract considerable controversy in the science world. John Derbyshire wrote that as a result of the findings, “our cherished national dream of a well-mixed and harmonious meritocracy may be unattainable.” Richard Lewontin considers the two published papers as “egregious examples of going well beyond the data to try to make a splash.” Bruce Lahn maintains that the science of the studies is sound, and freely admits that a direct link between these particular genes and either cognition or intelligence has not been clearly established. Lahn is now engaging himself with other areas of study. Later studies have not found those gene variants to be associated with mental ability or cognition.

Later genetic association studies by Mekel-Bobrov et al. and Evans et al. also reported that the genotype for MCPH1 was under positive selection. An analysis by Timpson et al., found “no meaningful associations with brain size and various cognitive measures”. A later 2010 study by Rimol et al. demonstrated a link between brain size and structure and two microcephaly genes, MCPH1 (only in females) and CDK5RAP2 (only in males). In contrast to previous studies, which only considered small numbers of exonic single nucleotide polymorphisms (SNPs) and did not investigate sex-specific effects, this study used microarray technology to genotype a range of SNPs associated with all four MCPH genes, including upstream and downstream regulatory elements, and allowed for separate effects for males and females.

https://en.wikipedia.org/wiki/Microcephalin

I knew it was debated what the genes were actually doing, but I’m more interested in the suggestion they swept through the whole population of humans well after the Australian Aboriginal people were isolated away here.

Continental Sahul lasted until 11,000 years ago and there’s no suggestion that there wasn’t constant people movement across the Sunda Strait until then. Macassans were interacting with indigenous Australians to until very recently.

It’s quite likely that there has been little research in this area amongst indigenous Australian populations.

For example in this paper from 2021:

In order to check this hypothesis, we started from the genetic data in , consisting of the
frequency of the two “derived” alleles in 59 populations, relatively widespread across the globe,
but with a clear bias towards Africa and Eurasia, and very little data from the Americas and the
Pacific, and no data from Australia.

Tone and genes: New cross-linguistic data and
methods support the weak negative effect of
the “derived” allele of ASPM on tone, but not of
Microcephalin

https://pdfs.semanticscholar.org/bb21/0e4d1585b4f8dbc4d7acf8b079beb2d8f362.pdf

Witty Rejoinder said:

buffy said:

Bubblecar said:

From Wikipedia:

Controversy

The research results began to attract considerable controversy in the science world. John Derbyshire wrote that as a result of the findings, “our cherished national dream of a well-mixed and harmonious meritocracy may be unattainable.” Richard Lewontin considers the two published papers as “egregious examples of going well beyond the data to try to make a splash.” Bruce Lahn maintains that the science of the studies is sound, and freely admits that a direct link between these particular genes and either cognition or intelligence has not been clearly established. Lahn is now engaging himself with other areas of study. Later studies have not found those gene variants to be associated with mental ability or cognition.

Later genetic association studies by Mekel-Bobrov et al. and Evans et al. also reported that the genotype for MCPH1 was under positive selection. An analysis by Timpson et al., found “no meaningful associations with brain size and various cognitive measures”. A later 2010 study by Rimol et al. demonstrated a link between brain size and structure and two microcephaly genes, MCPH1 (only in females) and CDK5RAP2 (only in males). In contrast to previous studies, which only considered small numbers of exonic single nucleotide polymorphisms (SNPs) and did not investigate sex-specific effects, this study used microarray technology to genotype a range of SNPs associated with all four MCPH genes, including upstream and downstream regulatory elements, and allowed for separate effects for males and females.

https://en.wikipedia.org/wiki/Microcephalin

I knew it was debated what the genes were actually doing, but I’m more interested in the suggestion they swept through the whole population of humans well after the Australian Aboriginal people were isolated away here.

Continental Sahul lasted until 11,000 years ago and there’s no suggestion that there wasn’t constant people movement across the Sunda Strait until then. Macassans were interacting with indigenous Australians to until very recently.

There is a bit about that stuff in this article.

Australia’s isolation was relative. There appear to have been multiple waves into the Sahul, and the land bridge between Aust and New Guinea only went away some 12000 years ago. There was also a big influx from the Indian Sub-cpntinent around 5000 years ago, for some reason.