Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) GM3 synthase deficiency ?
    ### Response:
    GM3 synthase deficiency is characterized by recurrent seizures (epilepsy) and problems with brain development. Within the first few weeks after birth, affected infants become irritable and develop feeding difficulties and vomiting that prevent them from growing and gaining weight at the usual rate.
    