London, August 12 (ANI): DNA analysis of ancient remains shows that Neanderthals shared with modern humans the gene that gives the ability to taste bitter flavors.
Most people find the chemical, known as PTC, very bitter, but 25 percent cannot taste it at all.
According to a report by BBC News, analysis of the 48,000 year-old bone shows that the genetic variation responsible for this difference also existed in Neanderthals.
Dr Carles Lalueza-Fox from the Institut de Biologia Evolutiva in Barcelona said that this means that this genetic variation predates the divergence of the lineages leading to Neanderthals and modern humans.
"The non-taster is not something that occurs just in modern populations. It is something that was present at least half a million years ago," Dr Lalueza-Fox told BBC News.
The gene TAS2R38 encodes for a protein in the taste receptors on the tongue which allows us to taste bitterness.
In people who are non-tasters, a recessive variant of the gene results in a functional change to the amino acids so that the protein is different and cannot bind to the bitter substance.
The researchers describe how they amplified and sequenced the TAS2R38 gene from a Neanderthal bone sample found at El Sidron in northern Spain.
The remains of 11 Neanderthal individuals have been excavated from this site since 2000.
Scientists are confident the sample was not contaminated with any modern human DNA as the remains were excavated under sterile conditions and immediately frozen.
The presence of the gene means that this particular Neanderthal individual could taste bitter flavors.
But, researchers also determined that he carried the recessive gene which blocks this ability.
This means that the Neanderthal population must have contained individuals unable to taste bitterness.
The chemical in question is phenylthiocarbamide, or PTC. Forms of it are found in leafy vegetables like sprouts and broccoli and in some poisonous plants.
The ability to taste the chemical would help individuals avoid eating large quantities of toxic plants.
But, the researchers said that the fact that the recessive form of the gene has survived in modern humans must mean that there is some genetic advantage in not being able to taste bitter flavours. (ANI)