A Novel Splice-Site Variant in SLC12A6 Causes Andermann Syndrome without Agenesis of the Corpus Callosum

Abstract

Andermann syndrome, otherwise known as agenesis of the corpus callosum with peripheral neuropathy (ACCPN), is an autosomal recessive motor and sensory neuropathy known to be associated with ACC and mild-to-moderate intellectual disability. We present a 7-year-old girl with infantile-onset hypotonia, mild intellectual disability, and severe motor and sensory demyelinating peripheral neuropathy. Brain magnetic resonance imaging showed intact corpus callosum. Whole exome sequencing showed a novel splice-site pathogenic variant in the SLC12A6 gene. We confirm that ACC is not a mandatory feature and suggest that the term ACCPN may be misleading.

Keywords

Andermann syndrome - motor and sensory demyelinating neuropathy - agenesis of the corpus callosum - SLC12A6 - KCC3

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