“Mutations in Metabotropic Glutamate Receptor 1 Contribute to Natural Short Sleep Trait”, 2020-10-15 (; similar):
2 independent mutations found in GRM1 cause familial natural short sleep
Both mGluR1 mutations have less activity than wild-type receptors in vitro
Both mutant mouse models have shorter sleep duration than control mice
Brain slices from mutant mice showed increased excitatory synaptic transmission
Sufficient and efficient sleep is crucial for our health. Natural short sleepers can sleep substantially shorter than the average population without a desire for more sleep and without any obvious negative health consequences.
In searching for genetic variants underlying the short sleep trait, we found 2 different mutations in the same gene (metabotropic glutamate receptor 1) from 2 independent natural short sleep families.
In vitro, both of the mutations exhibited loss of function in receptor-mediated signaling. In vivo, the mice carrying the individual mutations both demonstrated short sleep behavior. In brain slices, both of the mutations changed the electrical properties and increased excitatory synaptic transmission.
These results highlight the important role of metabotropic glutamate receptor 1 in modulating sleep duration.
[Keywords: mGluR1, loss-of-function, short-sleep]