SCA2 is not a major locus for ADCA type I in French families
- INSERM, Paris (France); and others
Autosomal dominant cerebellar ataxias (ADCA) of type I, a group of clinically heterogeneous neurodegenerative disorders, are known to be genetically heterogeneous since a second locus for ADCA type I (SCA2) has been identified on the long arm of chromosome 12. Linkage analysis was performed in 7 French ADCA type I families in order to estimate its frequency. We analysed 121 individuals, 39 of whom were affected. In 6 families, the SCA2 candidate interval, spanning 12.8 cM, was excluded by bi- and multipoint analysis. In one family (SAL-315), however, the maximal positive lod score reached 2.03 at the D12S79 locus. A posterior probability of 94% in favor of linkage to SCA2 was calculated by homogeneity analysis. The clinical profile of this family was similar to that of previously described SCA1 and non-SCA1 families, except that dementia was observed in 2 out of 6 patients. This may be a clinical idiosyncrasy in this family and was insufficient for a genotype-phenotype correlation. 14 refs., 1 fig., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 254381
- Journal Information:
- American Journal of Medical Genetics, Vol. 60, Issue 5; Other Information: PBD: 9 Oct 1995
- Country of Publication:
- United States
- Language:
- English
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