Postural instability and backward leaning in a patient of familial fatal insomnia with positive SOX1 antibodies

Abstract

• First report on Met/Met patient of FFI with postural instability and backward leaning from disease onset. • The phenotypic spectrum of homozygous FFI may be broader and more variable than previously described. • Positive anti-SOX1 in serum of FFI points the complicated association between prionopathies and immune-related factors.