Is the voice inherited? A study calculated for the first time the heritability of the anatomical structure of the vocal tract of 632 monozygotic and dizygotic twins and verified the importance of genetics, but also the influence of the environment or customs.
The study, published in the journal “Human Genetics”opens up new perspectives to understand the interaction between genetics, environment and culture that shape the vocal tract, the system made up of cavities and organs such as the tongue, larynx or lips that determine speech and language.
The research was directed by Dan Dediu, researcher at the Faculty of Philology and Communication of the University of Barcelona (UB), and the professor at the Free University of Amsterdam, Dorret boomsmawho pointed out that, despite its importance for speaking, breathing and eating, little is known about the genetics of the human vocal tract.
The study, in which they participated geneticists, neuroscientists and linguistswas derived from data collected in five twin studies by the Twin Registry of the Netherlands, which included monozygotic twins, who are nearly genetically identical, and dizygotic twins, who share an average of 50% of the genome.
researcher Emily Jennings clarified that “the analysis in the two types of twins allows us to know the importance of genetics and the environment to explain the differences between people in the anatomy of the vocal tract”.
To measure aspects of the vocal tract that aren’t externally visible, the scientists analyzed 3D MRI imagesthat capture the anatomical characteristics of the soft and rigid structures of all the organs that make up the way of speaking.
For six months they marked the images to identify defined anatomical structures and describe curves and surfaces and obtained measurements such as distances, angles, curvatures or proportions, which allowed them to capture the size and shape of the structures of the speech system.
The results provided new evidence on the contributions of genetic and environmental factorswhich surprised the researchers themselves.
“The location of the larynx it appears to be under strong genetic influence, while dental arches or lavish vaults have low heritability, “summarized the researchers.
According to previous studies, dental carethe type of diet and also the custom of thumb sucking in childhood have a noticeable effect on the structure of the vocal tract.
However, “there are other bony structures, such as the nasal cavity and jawwhich appear to be quite resistant to these environmental influences, “said the researchers.
These results prove it genetics matter, but it doesn’t control everything, and that it is necessary to look for the mechanisms through which biology, environment and culture interact.
The methodology and programs developed during the study they are freely available to any interested researcher, so that “each group can apply exactly the same methodology to their samples, which makes it possible to reproduce and extend our study,” said Dediu.
“Moreover – added the researcher – this protocol could help in the future to identify, diagnose and follow pathologies affecting the vocal tract“. EFE
Source: Clarin
