After analyzing the DNA of 95,000 individuals, geneticists in London and Switzerland identified a genetic mutation that leads to "extreme skinniness". Over the last few years, there have been several discoveries of a predispostion to obesity caused by genetic mutations, but this is the first time they found a discernible link between "skinny genes" and an underweight frame.
The research suggests that there are 28 genes in chromosome 13 that help determine the mutation. If someone is missing these genes they tend to be overweight. However, if they have duplicates of these genes, they are genetically coded to becoming very thin adults. A healthy BMI is known to be between 18.5 and 25, but individuals with this “skinny gene” typically have a BMI less than 18.5.
Although this might sound like a dream come true to the millions of adults who suffer from above-average body fat levels, the data suggest that the duplication mutation is associated with several unpleasant and serious medical conditions. These include microephaly and “failure to thrive” - in which children are expected to live significantly shorter lives.
Hopefully this research continues so we can gain better insight into the genetic foundations of obesity and its counterpart.