Usher syndrome is a genetic disorder that affects both hearing and vision. It is characterized by hearing loss at birth or early childhood, followed by progressive vision loss due to a condition called retinitis pigmentosa. This condition causes the gradual degeneration of the retina, leading to difficulties in seeing in low light and peripheral vision loss. There are three main types of Usher syndrome, classified by the severity of symptoms and the age of onset. Type 1 typically involves profound hearing loss and early vision loss, while Type 2 has moderate hearing loss and later onset of vision issues. Type 3 presents variable hearing and vision loss over time.