A 59 year old woman presented with an atypical parkinsonian syndrome with clinical and neuroimaging features of corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP). CBS manifestations were slurred/scanning speech and asymmetrical right signs: levitation phenomena, pseudo-hemiparetic gait and hypertonia/hyperreflexia. PSP signs were staring face and oculomotor apraxia. Neuroimag...

congenital ocular motor apraxia (COMA), is characterized by the inability to initiate horizontal saccades on command with preserved vertical eye movements and generally preserved smooth ocular pursuit.1,2 Random spontaneous saccades may be seen in some patients with ISID. Although the term ‘congenital ocular motor apraxia’ is commonly used in the medical literature, it is inaccurate because the...

Bipedal locomotion and fine motility of hand and larynx of humans introduced musculoskeletal adaptations, new pyramidal, corticostriatal, corticobulbar, nigrostriatal, and cerebellar pathways and expansions of prefrontal, cingular, parieto-temporal and occipital cortices with derived new brain capabilities. All selectively degenerate in aged homo sapiens following 16 syndromic presentations: (1...

Two brothers are described who during their fourth decade presented with isolated down beat nystagmus and later developed a progressive cerebellar ataxia. The nature of this unusual oculomotor disorder and its rare occurrence in other inherited conditions are discussed.

Patients harboring A467T and W748S POLG1 mutations present with a broad variety of neurological phenotypes, including cerebellar ataxia, progressive external ophthalmoplegia (PEO), myoclonus, epilepsy, and peripheral neuropathy. With exception of ataxia and myoclonus, movement disorders are not typical features of POLG1 associated disorders. We report on two affected siblings compound heterozyg...

We report a patient with unilateral midbrain hemorrhage which caused ipsilateral complete oculomotor nerve palsy with pupillary involvement, contralateral upgaze paresis, contralateral limb ataxia and Parinaud’s syndrome. CT scan and MRI brain demonstrated a hemorrhage in the left paramedian midbrain probably involving the oculomotor fascicles; extension of the hemorrhage to the most rostral mi...

Arl13b belongs to the ADP-ribosylation factor family within the Ras superfamily of regulatory GTPases. Mutations in Arl13b cause Joubert syndrome, which is characterized by congenital cerebellar ataxia, hypotonia, oculomotor apraxia, and mental retardation. Arl13b is highly enriched in cilia and is required for ciliogenesis in multiple organs. Nevertheless, the precise role of Arl13b remains el...

Senataxin, mutated in the human genetic disorder ataxia with oculomotor apraxia type 2 (AOA2), plays an important role in maintaining genome integrity by coordination of transcription, DNA replication, and the DNA damage response. We demonstrate that senataxin is essential for spermatogenesis and that it functions at two stages in meiosis during crossing-over in homologous recombination and in ...