GM2 gangliosidoses: evaluation of clinical, biochemical and genetic findings of patients with three novel mutations

Abstract

Purpose: The aim of this study is to evaluate the diagnosis characteristics, clinic findings, phenotypical and genotypical features of children with GM2 gangliosidoses. Materials and Methods: The file records of 14 patients diagnosed with GM2 gangliosidoses in our clinic were retrospectively reviewed. The GM2 gangliosidoses diagnosis was confirmed by determining the levels of serum total hexosaminidase and β-hexosaminidase activity with genetic analysis. Results: We identified a total of seven different mutations, three of which were novel (one in the HEXA gene and two in the HEXB gene) in 14 patients. We found a high frequency of c.1100_1111del (p.Gly367_Tyr370del) mutation in HEXA affected patients. The mean age at diagnosis was 13.46.3 months and 14.24.2 months for patients with Tay–Sachs disease (TSD) and Sandhoff disease (SD) respectively. Neuroregression was present in 92.9% of our patients. Of the 14 patients, 11 had epilepsy, 10 had developmental delay, 6 had hyperacusis, 6 had cherry-red spots and 6 had macrocephaly, but none of the patients had organomegaly. Conclusion: GM2 gangliosidoses disease should be considered for children with developmental regression and/or delay. For early diagnosis, enzyme analysis and gene detection should be performed in children with suspected GM2 gangliosidoses in the presence of clinical findings.

Keywords

• lysosomal storage disorders
• gm2 gangliosidoses
• hexosaminidase
• tay-sachs disease
• sandhoff disease
• lizozomal depo hastalıkları
• gm2 gangliosidoz
• hekzosaminidaz
• tay-sachs hastalığı; sandhoff hastalığı