Joubert syndrome-related disorders (JSRD) is a very rare syndrome observed with agenesis of the vermis,episodic hyperpnea, abnormal eye movements, and cerebellar ataxia and mental retardation. There have been many reports on the image-based diagnosis using MRI/CT, but not many clinical reports on the intelligence of subjects with JSRD. We herein report a clinically mild form of JSRD in a 7-year-old female. The patient did not have any clinical abnormalities in the neonatal period.She initially visited the neurology outpatient department at 6 months of age because her neck was still unstable. A brain MRI was conducted to assess symptoms of abnormal eye movements and body trunk cerebella rataxia, and she was diagnosed with JSRD based on the observation of agenesis of the vermis and characteristic molar tooth signs. Regarding her motor development, she was able to hold her head up at 7months of age, and was able to sit up at 1 year and 2 months old. She underwent rehabilitation, and a wide base cerebellar gait was observed when she was 5 years old. In addition, at 5 years of age, she could intermittently speak two-word sentences, draw pictures with an understanding of color, and was able to engage in actions such as throwing a ball. At 6 years of age, her conversation became better. She entered elementary school at 7 years of age, was able to go up and down stairs, read words, do single-digit addition, and write many Chinese characters with a pencil. The intellectual dysfunction of subjects with JSRD is generally moderate to severe. Thus, this case was diagnosed to be a clinically mild form of JSRD, because the patient exhibited limited effects on her intelligence
