Marinesco-Sjögren syndrome due to SIL1 mutations with a comment on the clinical phenotype.
BACKGROUND
Marinesco-Sjögren syndrome is an autosomal recessive cerebellar ataxia, characterised by cerebellar ataxia, myopathy, cataracts and intellectual disability, due to mutations in the SIL1 gene.


METHODS
The clinical features and two novel SIL1 mutations of four Dutch patients with Marinesco-Sjögren syndrome are described and compared to the literature on genetically proven Marinesco-Sjögren patients.


RESULTS
The core phenotype of this syndrome appears homogeneous, but: [1] cataract can develop later than the motor and cognitive signs; [2] myopathy is an early feature that seems progressive during the course of the disease; [3] serum creatine kinase is normal or only mildly elevated; [4] peripheral neuropathy is absent; and [5] a variable degree of intellectual disability is present in most Marinesco-Sjögren patients.


CONCLUSIONS
Because the late appearance of some hallmarks and the uncertainty as to whether incomplete phenotypes occur, SIL1 mutation analysis is helpful early in the diagnostic work-up of children with suspected inherited ataxias.
Department of Paediatric Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, PO Box 9101, 6500HB Nijmegen, The Netherlands.
M
M
Horvers
A K
AK
Anttonen
A E
AE
Lehesjoki
E
E
Morava
S
S
Wortmann
S
S
Vermeer
B P
BP
van de Warrenburg
M A
MA
Willemsen
D000328:Adult; D002648:Child; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D010641:Phenotype; D013132:Spinocerebellar Degenerations / Q000150:complications* / Q000235:genetics* / Q000473:pathology*
D020662:Guanine Nucleotide Exchange Factors; C418483:SIL1 protein, human