Importantly, the Thra1+/m mice present all features observed in humans with THRA mutation-mediated RTH syndrome (growth retardation, impairment of motor coordination, metabolic changes, skeletal abnormalities and cognitive dysfunction while the circulating hormone level is near-normal), and therefore provide an excellent mouse model for investigating therapeutic treatments of neurological disorders observed in patients with unliganded THRA1 activity or the larger patient population with TH deficiency during development. Here, THRA is linked to tyrosine hydroxylase deficiency.