Why You Are Short (Or Tall): Human Genetics, Explained

If you feel you’re too short — or too tall — you can blame your genes. And it looks like there’s plenty of blame to go around.

A study in Nature has identified dozens of infrequently occurring genetic variants that are associated with human height to a moderate or large degree, some of them carrying an influence of up to 2 centimeters (more than ¾ of an inch). A number of the DNA elements are tied to genes already known to affect growth, such as those affecting bones and hormones, but others represent new processes involved in growth and height. That latter group could potentially lead scientists to new treatments for growth disorders.

Read: Technology To Change Genes Could End Tuberculosis

“In the context of precision medicine, the results also bring hope to understand the genetic basis of complex diseases such as diabetes or schizophrenia,” according to the Swiss Institute of Bioinformatics. “The idea is that if we can understand the genetics of a simple human trait like height, we could then apply this knowledge to develop tools to predict complex human diseases,” researcher Zoltán Kutalik said in the institute’s statement.

According to SIB, the research relied on the international effort of more than 300 scientists and pulled DNA data from more than 700,000 people.

giraffe-1955126_1920 Your body might contain genes that can add up to 2 centimeters to your height. Pixabay, public domain

While previous research has fingered hundreds of genetic variants for playing a role in height, the Nature study notes that those variants are much more common, but play only a marginal role in a person’s measurement. The newly discovered variants have “greater than 10 times the average effect of common variants.”

While DNA plays the biggest role in how tall we are, our diet and our environment also influence how we measure up. For instance, Scientific American notes that protein is the “most important nutrient for final height.” Minerals such as calcium, vitamin A and vitamin D are also significant. “Because of this, malnutrition in childhood is detrimental to height.”

Source: Marouli E, Graff M, Medina-Gomez C, et al. Rare and low-frequency coding variants alter human adult height. Nature. 2017.

See also:

Genes Tell Us Whether You’ll Drop Out of School

How a Blood Transfusion Changes Your DNA

How Evolution Will Change Our Bodies

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