Have you ever wondered what determines your height? Recent breakthroughs in genetics may have the answer.
Scientists from the Broad Institute at MIT and Harvard used data from the Genetic Investigation of Anthropometric Traits consortium (GIANT) to analyze genetic information from more than 700,000 people. What they discovered were 83 DNA alterations that contribute to determining a person’s height.
The study, published in the journal Nature, identified rare genetic variants that seem to have a large effect on human growth, adding to the 700 common genetic factors that all impact how tall you will become.
Dr. Joel Hirschhorn, the study’s lead author and a professor of pediatrics and genetics at Boston Children’s Hospital and Harvard Medical School, said that “common variants still contribute more to height than rare variants.”
But for people who carry one of the rare variants, Hirschhorn explained that “the impact can be much greater than for common variants,” often leading to changes in height of up to an inch, as opposed to a millimeter for the common variants.
The team utilized a new technology called the ExomeChip that allowed them to scan the genomes of large populations to find rare markers that correlated with particular heights. In their research, they identified 51 uncommon variants found in less than 5 percent of people, and 32 rare variants found in less than 0.5 percent of the population.
The study served to show that we inherit most of the factors that influence our height, though variations do exist. “In places where most people get enough nutrition in childhood to grow to their potential, about 80 percent or more of the variability in height is due to genetic factors that we inherit from our parents,” Hirschhorn said, with the remaining 20 percent being influenced by other factors.
Studies such as this hold promise for applying the same techniques to investigate rare DNA changes involved in diseases and health issues, which could help to produce better treatments and shed more light on how such diseases spread.
Top photo by Peter Macdiarmid
Lauren Leising is a freelance writer based in Athens, Georgia.