title: An Unusual Developmental Profile of Salla Disease in a Patient with the SallaFIN Mutation.
abstract: Salla disease (SD) is a disorder caused by defective storage of free sialic acid and results from mutations in the SLC17A5 gene. Early developmental delay of motor functions, and later cognitive skills, is typical. We describe a developmental profile of an unusual homozygous patient, who harboured the SallaFIN (p.R39C) mutation gene. The study involved neurological examination, neuropsychological investigation, and brain imaging. The neurocognitive findings were atypical in comparison with other patients with the SallaFIN mutation. Interestingly, there was no deterioration in the patient's neurological condition during adulthood. Her neurocognitive skills were remarkably higher than those of other patients with a conventional phenotype of SD. Our results suggest that the phenotype of SD is broad. Unidentified genetic or environmental variation might explain the unique SD type of this case.
authors.affiliation: Department of Neurology, Oulu University Hospital, P.O. Box 20, 90029 Oulu, Finland ; Department of Clinical Medicine, Neurology, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland.
authors.forename: Liisa E
authors.initials: LE
authors.lastname: Paavola
authors.forename: Anne M
authors.initials: AM
authors.lastname: Remes
authors.forename: Pirkko H
authors.initials: PH
authors.lastname: Sonninen
authors.forename: Vesa V
authors.initials: VV
authors.lastname: Kiviniemi
authors.forename: Tapio T
authors.initials: TT
authors.lastname: Korhonen
authors.forename: Kari
authors.initials: K
authors.lastname: Majamaa