Sanfilippo syndrome type C

General Information (adopted from Orphanet):

Synonyms, Signs: MPS IIIC
SANFILIPPO SYNDROME C
MPS3C
Mucopolysaccharidosis type 3C
HGSNAT deficiency
ACETYL-CoA:ALPHA-GLUCOSAMINIDE N-ACETYLTRANSFERASE DEFICIENCY
Heparan-alpha-glucosaminide N-acetyltransferase deficiency
Number of Symptoms 49
OrphanetNr: 79271
OMIM Id: 252930
ICD-10: E76.2
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: No data available.
Inheritance: Autosomal recessive
[Orphanet]
Age of onset:

Disease classification (adopted from Orphanet):

Parent Diseases: Mucopolysaccharidosis type 3
 -Rare bone disease
 -Rare developmental defect during embryogenesis
 -Rare eye disease
 -Rare genetic disease
 -Rare neurologic disease

Symptom Information: Sort by abundance 

1
 (HPO:0002159) Heparan sulfate excretion in urine 12 / 7739
2
 (HPO:0000250) Dense calvaria 6 / 7739
3
 (HPO:0000280) Coarse facial features 189 / 7739
4
 (HPO:0000664) Synophrys 112 / 7739
5
 (HPO:0002788) Recurrent upper respiratory tract infections 31 / 7739
6
 (HPO:0000232) Everted lower lip vermilion 90 / 7739
7
 (HPO:0000268) Dolichocephaly 144 / 7739
8
 (HPO:0000510) Rod-cone dystrophy 266 / 7739
9
 (HPO:0000365) Hearing impairment 539 / 7739
10
 (HPO:0002371) Loss of speech 15 / 7739
11
 (HPO:0002360) Sleep disturbance 113 / 7739
12
 (HPO:0000752) Hyperactivity 140 / 7739
13
 (HPO:0001249) Intellectual disability 1089 / 7739
14
 (HPO:0001270) Motor delay 322 / 7739
15
 (HPO:0002333) Motor deterioration 7 / 7739
16
 (HPO:0002015) Dysphagia 301 / 7739
17
 (HPO:0001250) Seizures 1245 / 7739
18
 (HPO:0003309) Ovoid thoracolumbar vertebrae 6 / 7739
19
 (HPO:0000943) Dysostosis multiplex 22 / 7739
20
 (HPO:0000900) Thickened ribs 9 / 7739
21
 (HPO:0002751) Kyphoscoliosis 131 / 7739
22
 (HPO:0001387) Joint stiffness 322 / 7739
23
 (HPO:0001744) Splenomegaly 337 / 7739
24
 (HPO:0002240) Hepatomegaly 467 / 7739
25
 (HPO:0002014) Diarrhea 225 / 7739
26
 (HPO:0001507) Growth abnormality 36 / 7739
27
 (HPO:0001007) Hirsutism 91 / 7739
28
 (HPO:0002208) Coarse hair 58 / 7739
29
 (HPO:0001670) Asymmetric septal hypertrophy 19 / 7739
30
 (HPO:0003653) Cellular metachromasia 2 / 7739
31
 (HPO:0100790) Hernia 9 / 7739
32
 (OMIM) Acetyl CoA:alpha-glucosaminidase N-acetyltransferase deficiency in fibroblasts 1 / 7739
33
 (HPO:0003828) Variable expressivity 130 / 7739
34
 (OMIM) Sleep disturbances common 3 / 7739
35
 (OMIM) Severe behavioral problems at age 3-4 2 / 7739
36
 (OMIM) Enzyme replacement therapy has not been effective 1 / 7739
37
 (OMIM) Slowing mental development by 1.5 to 3 years of age 3 / 7739
38
 (OMIM) Mild splenomegaly 6 / 7739
39
 (OMIM) Clear cornea 6 / 7739
40
 (OMIM) Fleshy nasal tip 1 / 7739
41
 (OMIM) Coarse facies, mild 3 / 7739
42
 (OMIM) Thickening of the helices 1 / 7739
43
 (OMIM) Loss of speech development 1 / 7739
44
 (OMIM) Dysostosis multiplex, mild (in some patients) 5 / 7739
45
 (OMIM) Hepatomegaly, mild 8 / 7739
46
 (OMIM) Usually normal stature 2 / 7739
47
 (OMIM) Temper tantrums 2 / 7739
48
 (OMIM) Metachromasia of white blood cells and fibroblasts 2 / 7739
49
 (HPO:0000007) Autosomal recessive inheritance 2538 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) Sanfilippo syndrome comprises several forms of lysosomal storage diseases due to impaired degradation of heparan sulfate. The deficient enzyme in Sanfilippo syndrome C, or MPS IIIC, is an acetyltransferase that catalyzes the conversion of alpha-glucosaminide residues to N-acetylglucosaminide ...
Diagnosis OMIM Klein et al. (1981) described an assay for the detection in leukocytes of homozygous and heterozygous carriers of Sanfilippo syndrome type C. Affected individuals had no residual activity of acetyl-CoA:alpha-glucosaminide N-acetyltransferase. The authors noted that the enzyme was ...
Clinical Description OMIM Kresse et al. (1976) reported 2 related patients of Greek origin with the phenotype of Sanfilippo syndrome who had normal values of heparan sulfamidase (605270) and alpha-N-acetylglucosaminidase (NAGLU; 609701). Metabolic correction was achieved upon cocultivation with Sanfilippo A ...
Molecular genetics OMIM Fan et al. (2006) identified the HGSNAT gene (610453), encoding the human N-acetyltransferase, and identified 2 mutations accounting for 4 alleles in 2 human MPS IIIC cell lines. A splice junction mutation (610453.0001) accounted for 3 mutant alleles, ...
Population genetics OMIM Using multiple ascertainment sources, Nelson et al. (2003) obtained an incidence rate for Sanfilippo syndrome (all forms combined) in western Australia for the period 1969 to 1996 of approximately 1 in 58,000 live births; there was a total ...