. . . . . . . "[In this review of PD, parkinsonian syndromes, essential tremor, AD, motor neurone disease (MND) and Huntington's chorea (HC) the following observations are made: 1). olfactory dysfunction is frequent and often severe in PD and AD; 2). normal smell identification in PD is rare and should prompt review of diagnosis unless the patient is female with tremor-dominant disease; 3). anosmia in suspected progressive supranuclear palsy and corticobasal degeneration is atypical and should likewise provoke diagnostic review; 4). hyposmia is an early feature of PD and AD and may precede motor and cognitive signs respectively; 5). subjects with anosmia and one ApoE-4 allele have an approximate 5-fold increased risk of later AD; 6). impaired smell sense is seen in some patients at 50% risk of parkinsonism; 7). smell testing in HC and MND where abnormality may be found, is not likely to be of clinical value; and 8). biopsy of olfactory nasal neurons shows non-specific changes in PD and AD and at present will not aid diagnosis.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2017-02-19"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2017-10-17T13:10:34+02:00"^^ . . . . . . . . . . . "v5.0.0.0" . "v5.0.0" .