Genetics: A genetic explanation for below average height in Peruvian individuals

A genetic variant associated with lower height in the population of Peru is identified in a study published this week in Nature. People who have two copies (that is, are homozygous) of this variant were found to be, on average, 4.4 cm shorter than average.

The population of Peru is among the shortest in the world, with average heights of 165.3 cm and 152.9 cm for men and women, respectively. However, the specific genes and processes responsible for this phenomenon remain unclear.

In order to determine the genetic factors that may contribute to height in this population, Soumya Raychaudhuri and colleagues obtained genetic data and the heights of 3,134 individuals in Lima, Peru. By performing a genome-wide association study the authors identified a mutation in the FBN1 gene, which encodes a protein involved in the extracellular matrix—a framework that supports cells and regulates their growth. They then confirmed their association in an independent cohort of 598 Peruvians. The variant (E1297G) was found to reduce height by 2.2 cm per allele.

The authors then compared the frequency of the mutation among 150 people from three different geographical regions in Peru: the Amazon (28 individuals), coast (46 individuals) and Andes (76 individuals). Here, they found that the variant was more frequent in the coastal population and suggest that shorter stature might be the result of adaptation to factors associated with the coastal environment.