London Jun 12 (IANS): An international team of researchers has identified mutations in a gene that influences the pitch of voices.

Speaking is one of the most characteristic human behaviours, and yet the genetic underpinnings of voice and speech are largely unknown.

The study, published in the journal Science Advances, revealed the discovery of sequence variants in the gene ABCC9 that influence the pitch of voices.

The team led by deCODE genetics, the genomics company in Reykjavik, that carried out the investigation, combined speech recordings from almost 13,000 Icelanders with data, in the sequence of the genome, to search for common variants in ABCC9 that are associated with a higher-pitched voice.

The scientists found that ABCC9 variants are associated with higher voice pitch in both men and women.

The same sequence variants are also linked to higher pulse pressure, a cardiovascular risk factor, highlighting links between voice pitch and health-related traits.

In addition to voice pitch, the study investigated the genetics of vowel acoustics.

While vowel sounds such as ah or ee are clearly influenced by culture and context, the scientists found that such measures contain a heritable component, which likely has to do with the shape of the vocal tract and its effect on vowel sounds.

"This is the first time we know of a genetic variant that is really, truly affecting voice pitch" across a large population, Rosa Signy Gisladottir, a geneticist and linguist at deCODE Genetics was quoted as saying in a news article on Nature.

The findings shed new light on diversity in voice and speech and contribute to a better understanding of the human vocal system.

While how ABCC9 variants' link with higher voice pitch isn't clear, the team hypothesised that the gene ABCC9 contains instructions for making an ion channel that helps to ensure the proper functioning of the proteins collagen and elastin -- the proteins which help stretch tissues in the body -- a must for vocal cords to vibrate.

The increased heart conditions in such people may be due to the collagen and elastin, which while help heart muscles to move properly also can cause heart tissue to stiffen and malfunction if in higher quantity. This might also apply to the stretchy parts of vocal chords, Gisladottir was quoted as saying.