Scientists have discovered a mutation in the gene of the growth hormone receptor that may increase the life expectancy of men by an average of 10 years. This discovery is the result of a new study by Prof. Gil Atzmon of the University of Haifa. It was already known that the variants associated with the genetic pathways associated with growth hormone are also associated with longevity. According to Professor Atzmon a specific variant was found whose absence or presence is directly related to longevity.
Atzmon, head of the Laboratory for Genetics and Epigenetics of Aging and Longevity at Haifa University and other colleagues from the Albert Einstein Medical School, have already discovered that dysfunction in the biological paths that relate to HGH and insulin-like growth factor-1 (IGF-1) may contribute to longevity. So far, however, these pathways have only been tested in the laboratory and few mechanisms responsible for this process in the human body have been identified.
In this study, published in the journal Science Advances, scientists identified for the first time a genetic variant that alters the function of HGH and promotes longevity in males. The first research population founded by Professor Nir Barzilai in Einstein Medical School consisted of 102 100-year-old American Jewish men. The results were compared with three additional populations of 100-year-old from different parts of the world.
In all groups, removal of exon 3 from the GH receptor gene was found to be much more common in 100-year-old men but not in women compared to the 70 year olds control group. Indeed, people born with this variation outlived by ten years those without it. According to Professor Atzmon, this variation is certainly not the only cause of longevity, and many research participants have survived over 100 years without this variability. However, the presence of the variant guaranteed a long life with virtual certainty.
Research into the effect of the change has shown that it has an extraordinary effect. In nature, smaller strains of the same species generally live longer. For instance, smaller canine breeds live longer than larger breeds, ponies outlive horses and the same phenomenon occurs in different insects and rodents. In this case, the change in the receptors allowed the cells to absorb less growth hormone, but when the hormone was absorbed the protein expression was often greater. As a result people born with the mutation that lived about ten years longer than others were also about 3 cm taller than people born lacking the receptor.