No pathogenic GNAL mutations in 192 sporadic and familial cases of cervical dystonia.

We did not identify any mutations in GNAL that could be a cause of the dystonia in 192 cases drawn from the United Kingdom, including 84 familial cases. Our own data suggest that GNAL mutations do not represent a common cause of dystonia — in the U.K. population at least — and that the overall frequency of GNAL mutations may be closer to the figure obtained by Vemula et al[2] than the 15% initially reported by Fuchs et al.[1] This study also emphasises the importance of segregation analysis in establishing the pathogenicity or otherwise of novel variants and suggests that other novel genetic causes of dystonia remain to be identified.