A few studies have shown that the sound of voices have a hereditary link, and many of us have noticed that some family members have very similar voices. Although body size and hormones are known to play a role in how the human voice sounds, the genetic influences on human speech and voice have largely remained a mystery. New research reported in Science Advances has now expanded that understanding. This study has shown that small changes in the sequence of a gene called ABC9 can have an impact on voice pitch.
In this study, the researchers gathered individual recordings of about 13,000 Icelanders speaking, and combined that with each person's genetic data to look for sequence variants in a gene called ABC9 that are linked to voices with a higher pitch. The study was led by deCODE genetics, which has a wealth of genetic data from Icelanders. After a lengthy effort, about half of all the people living in Iceland have been a part of various genetics studies run by deCODE.
This work showed that variants in ABC9 are associated with higher voice pitches in men and women, and these variants were linked to a cardiovascular disease risk factor called higher pulse pressure. The study authors noted that there are connections between voice pitches and health traits.
The ABCC9 gene encodes for an ion channel that is involved in the function of collagen and elastin proteins, which are known to play a crucial role in the stretching action of different body tissues. The vibration of vocal chords is one example of that stretching.
The investigators also analyzed the genetics underlying vowel acoustics. They found that there is a heritable component to the pronunciation of the sounds of some vowels, like "ah" or "ee," even while there are obvious cultural and contextual influences on those sounds. The shape of the vocal tract is probably what leads to these characteristics.
This study has certainly improved our understanding of how the human vocal system is affected by genetics. The researchers noted that there are likely other genetic influences on vocal sounds that are still waiting to be revealed.
Sources: deCODE Genetics, Nature News, Science Advances