LZTR1 and schwannomatosis: Whereas the frequency of confirmed LZTR1-related schwannomatosis based on a birth incidence of schwannomatosis of 1 in 69,000 and the fact that around 27–30% of schwannomatosis cases are caused by LZTR1 [2] is less than 1 in 227,000, This means that <1% of those individuals with no family history or suggestive personal history of schwannomatosis and carrying a potential pathogenic LZTR1 variant are likely to develop schwannomatosis.