Genetic refinement of the hereditary neuralgic amyotrophy (HNA) locus at chromosome 17q25.

Hereditary neuralgic amyotrophy (HNA) is an autosomal dominant, recurrent focal neuropathy. HNA is characterised by episodes of painful brachial plexus neuropathy with muscle weakness and atrophy, as well as sensory disturbances. Single episodes are commonly preceded by non-specific infections, immunisations or parturition.