MedGen

Developmental delay, impaired speech, and behavioral abnormalities (DDISBA) is characterized by global developmental delay apparent from early childhood. Intellectual disability can range from mild to severe. Additional variable features may include dysmorphic facial features, seizures, hypotonia, motor abnormalities such as Tourette syndrome or dystonia, and hearing loss (summary by Cousin et al., 2021). [from OMIM]

An isometric tremor occurs with muscle contraction against a rigid stationary object (e.g., when making a fist). [from HPO]