The present review shows that hearing loss is a common feature of patients with TKS, a rare congenital syndrome presenting body and facial dysmorphism and hematological alterations due to a mutation of the CDC42 gene, which encodes an RHO family GTPase. Here, CDC42 is linked to macrothrombocytopenia-lymphedema-developmental delay-facial dysmorphism-camptodactyly syndrome.