We have a son in his 30s who has NS and was born profoundly deaf. Has there been any recent research into connection between the two?

Noonan syndrome with multiple lentignes or freckles (previously known as LEOPARD syndrome) has deafness as a feature and so we know that deafness may be associated with the PTPN11 gene. In most cases deafness in Noonan syndrome will simply be due to glue ear but it may be due to nerve deafness. There has not been much research on the nerve deafness in Noonan syndrome.