Autosomal recessive Cayman cerebellar ataxia, identified by Johnson et al. (1978) in a population isolate on Grand Cayman Island, is characterized by marked psychomotor retardation and prominent nonprogressive cerebellar dysfunction including nystagmus, intention tremor, dysarthria, and wide-based ataxic ... Autosomal recessive Cayman cerebellar ataxia, identified by Johnson et al. (1978) in a population isolate on Grand Cayman Island, is characterized by marked psychomotor retardation and prominent nonprogressive cerebellar dysfunction including nystagmus, intention tremor, dysarthria, and wide-based ataxic gait. Hypotonia is present from early childhood; retinal abnormalities are absent.
In individuals with Cayman ataxia, Bomar et al. (2003) found homozygosity for 2 sequence variants in the ATCAY gene: a ser301-to-arg (S301R) substitution and a splice site mutation in intron 9 (608179.0001). Both mutations completely segregated with the ... In individuals with Cayman ataxia, Bomar et al. (2003) found homozygosity for 2 sequence variants in the ATCAY gene: a ser301-to-arg (S301R) substitution and a splice site mutation in intron 9 (608179.0001). Both mutations completely segregated with the disorder and with carrier status in over 40 family members who were genotyped blindly. Neither mutation was found in any of more than 1,000 chromosomes from several different ethnic groups.