TY - JOUR
T1 - Alpha-mannosidosis
T2 - correlation between phenotype, genotype and mutant MAN2B1 subcellular localisation
AU - Borgwardt, Line
AU - Stensland, Hilde Monica Frostad Riise
AU - Olsen, Klaus Juul
AU - Wibrand, Flemming
AU - Klenow, Helle Bagterp
AU - Beck, Michael
AU - Amraoui, Yasmina
AU - Arash, Laila
AU - Fogh, Jens
AU - Nilssen, Øivind
AU - Dali, Christine I
AU - Lund, Allan Meldgaard
PY - 2015
Y1 - 2015
N2 - BACKGROUND: Alpha-mannosidosis is caused by mutations in MAN2B1, leading to loss of lysosomal alpha-mannosidase activity. Symptoms include intellectual disabilities, hearing impairment, motor function disturbances, facial coarsening and musculoskeletal abnormalities.METHODS: To study the genotype-phenotype relationship for alpha-mannosidosis 66 patients were included. Based on the predicted effect of the mutations and the subcellular localisation of mutant MAN2B1 in cultured cells, the patients were divided into three subgroups. Clinical and biochemical data were collected. Correlation analyses between each of the three subgroups of genotype/subcellular localisation and the clinical and biochemical data were done to investigate the potential relationship between genotype and phenotype in alpha-mannosidosis. Statistical analyses were performed using the SPSS software. Analyses of covariance were performed to describe the genotype-phenotype correlations. The phenotype parameters were modelled by the mutation group and age as a covariate. P values of <0.05 were considered as statistically significant.RESULTS: Complete MAN2B1 genotypes were established for all patients. We found significantly higher scores in the Leiter-R test, lower concentrations of CSF-oligosaccharides, higher point scores in the Bruininks-Oseretsky Test of Motor Proficiency subtests (BOT-2); Upper limb coordination and Balance, and a higher FVC% in patients in subgroup 3, harbouring at least one variant that allows localisation of the mutant MAN2B1 protein to the lysosomes compared to subgrou 2 and/or subgroup 1 with no lysosomal localization of the mutant MAN2B1 protein.CONCLUSION: Our results indicate a correlation between the MAN2B1 genotypes and the cognitive function, upper limb coordination, balance, FVC% and the storage of oligosaccharides in CSF. This correlation depends on the subcellular localisation of the mutant MAN2B1 protein.
AB - BACKGROUND: Alpha-mannosidosis is caused by mutations in MAN2B1, leading to loss of lysosomal alpha-mannosidase activity. Symptoms include intellectual disabilities, hearing impairment, motor function disturbances, facial coarsening and musculoskeletal abnormalities.METHODS: To study the genotype-phenotype relationship for alpha-mannosidosis 66 patients were included. Based on the predicted effect of the mutations and the subcellular localisation of mutant MAN2B1 in cultured cells, the patients were divided into three subgroups. Clinical and biochemical data were collected. Correlation analyses between each of the three subgroups of genotype/subcellular localisation and the clinical and biochemical data were done to investigate the potential relationship between genotype and phenotype in alpha-mannosidosis. Statistical analyses were performed using the SPSS software. Analyses of covariance were performed to describe the genotype-phenotype correlations. The phenotype parameters were modelled by the mutation group and age as a covariate. P values of <0.05 were considered as statistically significant.RESULTS: Complete MAN2B1 genotypes were established for all patients. We found significantly higher scores in the Leiter-R test, lower concentrations of CSF-oligosaccharides, higher point scores in the Bruininks-Oseretsky Test of Motor Proficiency subtests (BOT-2); Upper limb coordination and Balance, and a higher FVC% in patients in subgroup 3, harbouring at least one variant that allows localisation of the mutant MAN2B1 protein to the lysosomes compared to subgrou 2 and/or subgroup 1 with no lysosomal localization of the mutant MAN2B1 protein.CONCLUSION: Our results indicate a correlation between the MAN2B1 genotypes and the cognitive function, upper limb coordination, balance, FVC% and the storage of oligosaccharides in CSF. This correlation depends on the subcellular localisation of the mutant MAN2B1 protein.
U2 - 10.1186/s13023-015-0286-x
DO - 10.1186/s13023-015-0286-x
M3 - Journal article
C2 - 26048034
SN - 1750-1172
VL - 10
SP - 70
JO - Orphanet Journal of Rare Diseases
JF - Orphanet Journal of Rare Diseases
ER -