Sialidosis Type I without a Cherry Red Spot— Is There a Genetic Basis?
- Author:
Koti NEERAJA
1
;
Vikram Venkappayya HOLLA
;
Shweta PRASAD
;
Bharath Kumar SURISETTI
;
Kempaiah RAKESH
;
Nitish KAMBLE
;
Ravi YADAV
;
Pramod Kumar PAL
Author Information
- Publication Type:3
- From:Journal of Movement Disorders 2021;14(1):65-69
- CountryRepublic of Korea
- Language:English
- Abstract: Sialidosis is an inborn error of metabolism due to a defect in the NEU1 gene and manifests as two phenotypes: mild type I and severe type II. The cherry red spot (CRS) is a characteristic feature in both types of sialidosis; reports of sialidosis without a CRS are rare. We report two cases of genetically confirmed sialidosis type I with a typical presentation of progressive cortical myoclonus and ataxia but without the CRS. A previously reported homozygous pathogenic variant p.Arg294Cys was detected in the first case, and a novel homozygous pathogenic variant p.Arg305Pro was detected in the second case. Additionally, we reviewed the literature describing cases with similar mutations to find a genetic basis for the absence of a CRS. Milder mutation of both alleles detected in both patients may be the reason for the absence of a CRS.
