IntroductionTransport and Golgi Organization Homolog 2 (TANGO2 ) deficiency is a rare genetic disorder with an autosomal recessive hereditary pattern that originates from biallelic pathogenic variants in the TANGO2 gene (OMIM: 616830) [1].Although the exact role of TANGO2 gene hasn’t been specified yet,TANGO2 deficiency disorder (TDD) can cause clinical findings such as developmental delays, seizure, life threatening rhabdomyolysis, hypothyroidism, different types of cardiac diseases which are the main reason for TDD mortality [1, 2].TDD was first described in 2016 and the incidence is estimated to be 1/1000000 with about 76 patients reported in medical studies[2, 3]. Even though most patients are involved with metabolic crises, seizures, and arrhythmias; not all the patients show a full TANGO2 -related phenotype[4]. 35% of patients in Dines et al study passed away before the age of 10 and the main reason was lethal arrhythmias leading to cardiac arrest [4].In this study we describe the clinical sequences of TDD case with homozygous allels from parents with heterozygous TANGO2 gene. Unlike most TDD cases that are commonly characterized with rhabdomyolysis and cardiac diseases[1], our case manifested no metabolic or cardiac disorder and the hallmark manifestation was episodes of seizure.