PO181 Spinocerebellar ataxia type 14: a novel mutation in the prkcg gene

Background

Spinocerebellar Ataxia Type 14 (SCA14) accounts for less than 1% of autosomal dominant cerebellar ataxia. It is caused by a heterozygous mutation of the Protein Kinase C Gamma (PRKCG) gene found on chromosome 19q13 and encodes a serine-threonine kinase.

Case

We present a family with an autosomal dominant pattern of cerebellar ataxia, of which 3 members, spanning 2 generations, have been found to have a novel complex mutation of the PRKCG allele, c.[381 G>T;394T>C] p.[ (Gln127His); (Ser132Pro)]. The age of onset of symptoms ranged from 30–50 years. They had a pure ataxic syndrome with evidence of limb dysmetria, saccadic eye movements and nystagmus, dysarthric speech and inability to tandem gait. All patients had slowly progressive symptoms. To date, no concerns have been raised with regards to cognitive dysfunction or myoclonus which have been reported in some cases of SCA14. MRI imaging demonstrated cerebellar atrophy in two of the three members.

Conclusions

Currently there are over 20 different mutations found on the PRKCG allele responsible for SCA14. We report report a further new mutation that is likely pathogenic in this family.