Early onset cerebellar ataxia with retained tendon reflexes: prevalence and gene frequency in an Italian population
Chiò, A.; Orsi, L.; Mortara, P.; Schiffer, D.
Clinical Genetics 43(4): 207-211
1993
ISSN/ISBN: 0009-9163 PMID: 8330454 Document Number: 421045
A genetic epidemiologic analysis of early onset cerebellar ataxis (EOCA) with retained tendon reflexes was performed in a defined area of North-western Italy. Forty cases diagnosed from 1940 to 1990 were ascertained. The ascertainment probability was 85.7%. The segregation analysis (Weinberg's proband method and 'singles' method under incomplete ascertainment) is compatible with autosomal recessive inheritance. The point prevalence ratio was 1.0/100,000 population. The birth incidence rate was 1/48,000 live births. Gene frequency was estimated to be 1/218. The ratio of first-cousin marriages among parents of EOCA (4.5%) was lower than expected using Dahlberg's formula (8.9%).