MedGen

Classic Joubert syndrome (JS) is characterized by three primary findings: A distinctive cerebellar and brain stem malformation called the molar tooth sign (MTS). Hypotonia. Developmental delays. Often these findings are accompanied by episodic tachypnea or apnea and/or atypical eye movements. In general, the breathing abnormalities improve with age, truncal ataxia develops over time, and acquisition of gross motor milestones is delayed. Cognitive abilities are variable, ranging from severe intellectual disability to normal. Additional findings can include retinal dystrophy, renal disease, ocular colobomas, occipital encephalocele, hepatic fibrosis, polydactyly, oral hamartomas, and endocrine abnormalities. Both intra- and interfamilial variation are seen. [from GeneReviews]

Senior-Loken syndrome-6 (SLSN6) is an autosomal recessive disorder characterized by the association of nephronophthisis resulting in end-stage renal disease in the second decade of life with retinal degeneration (Sayer et al., 2006). For a phenotypic description and a discussion of genetic heterogeneity of Senior-Loken syndrome, see 266900. [from OMIM]

Spinocerebellar ataxia-29 (SCA29) is an autosomal dominant neurologic disorder characterized by onset in infancy of delayed motor development and mild cognitive delay. Affected individuals develop a very slowly progressive or nonprogressive gait and limb ataxia associated with cerebellar atrophy on brain imaging. Additional variable features include nystagmus, dysarthria, and tremor (summary by Huang et al., 2012). For a general discussion of autosomal dominant spinocerebellar ataxia, see SCA1 (164400). [from OMIM]

Any COACH syndrome in which the cause of the disease is a variation in the TMEM67 gene. [from MONDO]

Absence or underdevelopment of the vermis of cerebellum. [from HPO]