A novel mutation in the DNMT1 gene in a patient presenting with pure cerebellar ataxia

ABSTRACT

Mutations in the DNA methyltransferase 1 gene (DNMT1) were reported to cause two phenotypes OMIM 604121 and OMIM 614116. The first phenotype includes autosomal dominant cerebellar ataxia, deafness, and narcolepsy, which were reported to be caused by mutations in exon 21. The second phenotype includes hereditary sensory and autonomic neuropathy type 1E, which was suggested to be caused by mutations in exon 20 and 21. In this article, we report a novel heterozygous missense variant c.898A>C, p.(Lys300Gln) in exon 12 of DNMT1 in a young woman who presented with pure cerebellar ataxia. This report indicates that a mutation in exon 12 may lead to pure cerebellar ataxia. Another possibility is that the patient is currently in an early stage of the disease, and as the disease progresses, she will have more manifestations. To confirm or exclude this possibility, a subsequent follow-up study reporting the disease progression in this patient may be needed. Further reports of cases with the same mutation are needed to confirm the phenotype of this mutation.