Some Neanderthals were probably redheads, a DNA study has shown. 
Writing in Science journal, a team of researchers extracted DNA from remains of two Neanderthals and retrieved part of an important gene called MC1R.
In modern people, a change - or mutation - in this gene causes red hair, but, until now, no one knew what hair colour our extinct relatives had.
By analysing a version of the gene in Neanderthals, scientists found that they also have sported fiery locks.
"We found a variant of MC1R in Neanderthals which is not present in modern humans, but which causes an effect on the hair similar to that seen in modern redheads," said lead author Carles Lalueza-Fox, assistant professor in genetics at the University of Barcelona.
Though once thought to have been our ancestors, the Neanderthals are now considered by many to be an evolutionary dead end.
They appear in the fossil record about 400,000 years ago and, at their peak, these squat, physically powerful hunters dominated a wide range spanning Britain and Iberia in the west, Israel in the south and Siberia in the east.
Our own species, Homo sapiens, evolved in Africa, and displaced the Neanderthals after entering Europe about 40,000 years ago. The last known evidence of Neanderthals comes from Gibraltar and is dated to between 28,000 and 24,000 years ago.
Writing in Science journal, a team of researchers extracted DNA from remains of two Neanderthals and retrieved part of an important gene called MC1R.
In modern people, a change - or mutation - in this gene causes red hair, but, until now, no one knew what hair colour our extinct relatives had.
By analysing a version of the gene in Neanderthals, scientists found that they also have sported fiery locks.
"We found a variant of MC1R in Neanderthals which is not present in modern humans, but which causes an effect on the hair similar to that seen in modern redheads," said lead author Carles Lalueza-Fox, assistant professor in genetics at the University of Barcelona.
Though once thought to have been our ancestors, the Neanderthals are now considered by many to be an evolutionary dead end.
They appear in the fossil record about 400,000 years ago and, at their peak, these squat, physically powerful hunters dominated a wide range spanning Britain and Iberia in the west, Israel in the south and Siberia in the east.
Our own species, Homo sapiens, evolved in Africa, and displaced the Neanderthals after entering Europe about 40,000 years ago. The last known evidence of Neanderthals comes from Gibraltar and is dated to between 28,000 and 24,000 years ago.
Altered chemistry
The latest research suggests that similar adaptations were evolved independently by Neanderthals and modern Europeans in response to similar environmental circumstances.
All humans carry the MC1R gene, but modern redheads possess an altered, or mutated, version of it.
This rare variant doesn't work as effectively as more common forms of the gene. This loss of function alters the chemistry of the cell, producing red hair and pale skin.
In the latest study, the authors retrieved fragments of the MC1R sequence from Neanderthal bones found at Monte Lessini in Italy and from remains unearthed at El Sidron cave in northern Spain. DNA is notoriously difficult to obtain from very old specimens such as these.
"This was a bit like finding a needle in a genomic haystack. I couldn't believe we found it the first time. I asked my friends to repeat the results. Eventually the variant was found in two separate Neanderthals in three different labs," said Dr Lalueza-Fox.
The latest research suggests that similar adaptations were evolved independently by Neanderthals and modern Europeans in response to similar environmental circumstances.
All humans carry the MC1R gene, but modern redheads possess an altered, or mutated, version of it.
This rare variant doesn't work as effectively as more common forms of the gene. This loss of function alters the chemistry of the cell, producing red hair and pale skin.
In the latest study, the authors retrieved fragments of the MC1R sequence from Neanderthal bones found at Monte Lessini in Italy and from remains unearthed at El Sidron cave in northern Spain. DNA is notoriously difficult to obtain from very old specimens such as these.
"This was a bit like finding a needle in a genomic haystack. I couldn't believe we found it the first time. I asked my friends to repeat the results. Eventually the variant was found in two separate Neanderthals in three different labs," said Dr Lalueza-Fox.
Unique variant
The researchers found that Neanderthals carried a unique variant of the gene not present in modern humans.
I
n order to test what effect it had on hair and skin colour, the researchers inserted the Neanderthal variant into a human cell called a melanocyte.
Melanocytes produce the dark pigment called melanin which gives skin, hair and eyes their colour.
The researchers saw the same loss of function in the Neanderthal form of MC1R as they did in modern variants of the gene which produce red hair.
"In Neanderthals, there was probably the whole range of hair colour we see today in modern European populations, from dark to blond right through to red," Dr Lalueza-Fox told the BBC News website.
To Dr Lalueza-Fox, the observation that the Neanderthal version of the gene is not found in modern humans suggests they did not interbreed with each other, as some scientists have proposed.
I
n order to test what effect it had on hair and skin colour, the researchers inserted the Neanderthal variant into a human cell called a melanocyte.Melanocytes produce the dark pigment called melanin which gives skin, hair and eyes their colour.
The researchers saw the same loss of function in the Neanderthal form of MC1R as they did in modern variants of the gene which produce red hair.
"In Neanderthals, there was probably the whole range of hair colour we see today in modern European populations, from dark to blond right through to red," Dr Lalueza-Fox told the BBC News website.
To Dr Lalueza-Fox, the observation that the Neanderthal version of the gene is not found in modern humans suggests they did not interbreed with each other, as some scientists have proposed.
BBC NEWS
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