MN1 C-terminal truncation syndrome is a novel neurodevelopmental and craniofacial disorder with partial rhombencephalosynapsis
A new study recently published in the Journal of Neurology identified a cluster of de novo truncating mutations in MN1 in a cohort of twenty three individuals with strikingly similar dysmorphic facial features, especially midface hypoplasia, and intellectual disability with severe expressive language delay. Imaging revealed an atypical form of rhombencephalosynapsis, a distinctive brain malformation characterized by partial or complete loss of the cerebellar vermis with fusion of the cerebellar hemispheres, in 8/10 individuals. The study suggested that the MN1 C-terminal truncation syndrome is not due to MN1 haploinsufficiency but is the result of dominantly acting C-terminally truncated MN1 protein.
- Brain. 2020 Jan 1;143(1):55-68