Why noses are like snowflakes
Noses look different, but only 4 genes determine each shape.
Cute and turned-up or long and hawkish? Round and bulbous or pointy and thin? It seems like there’s a different nose shape for almost every face.
But a new study from British researchers finds that although there are vast differences in the style of our noses, there are only four genes that determine nose shapes.
“What we’ve found are specific genes which influence the shape and size of individual features, which hasn’t been seen before,” study co-author Kaustubh Adhikari of University College London, a cell and developmental biologist, said in a statement.
The researchers analyzed more than 6,000 people in Brazil, Chile, Colombia, Mexico and Peru. The group included people of mixed ancestry, creating a wide range of facial features.
In addition to analyzing all the participants’ facial features, the researchers did 3-D reconstructions of 3,000 of the participants to get exact measurements.
The researchers uncovered four genes that mainly affect the width and pointiness of noses, as well as a fifth gene that has an impact on chin protrusion.
“Finding out the role each gene plays helps us to piece together the evolutionary path from Neanderthal to modern humans. It brings us closer to understanding how genes influence the way we look, which is important for forensics applications,” said Adhikari.
People have different shaped facial features for various reasons. It’s partially because of genetics, but it’s also due to the impact of how features evolved because of the environment.
The researchers point out that because the nose is key in regulating the temperature and humidity of the air we breathe, it developed different shapes in cooler and warmer climates.
“For example, the comparatively narrower nose of Europeans has been proposed to represent an adaptation to a cold, dry climate,” said lead researcher Andrés Ruiz-Linares, a biologist at University College London. “Identifying genes affecting nose shape provides us with new tools to examine this question, as well as the evolution of the face in other species”