Researchers of the Institute of Human Genetics Göttingen have identified a mutation in the MTOR gene as the causative genetic variation in a family with Smith-Kingsmore syndrome. This variant had previously been described in two other families. Smith-Kingsmore syndrome is a rare disorder characterized by macrocephaly, developmental delay and facial dysmorphism with autosomal dominant inheritance. In line with the previously reported findings, this recent study supports the presence of parental gonadal mosaicism as the underlying mechanism. Additionally, it suggests that the MTOR mutation might also cause intestinal polyps in affected individuals.

The study has now been published in the American Journal of Medical Genetics:

Smith-Kingsmore syndrome: A third family with the MTOR mutation c.5395G>A p.(Glu1799Lys) and evidence for paternal gonadal mosaicism
Moosa S, Böhrer-Rabel H, Altmüller J, Beleggia F, Nürnberg P, Li Y, Yigit G, Wollnik B.
Am J Med Genet A. 2016 Oct 18. doi: 10.1002/ajmg.a.37999. [Epub ahead of print]