rs770684838
Variant summary
Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1PM2PM5PP3_StrongPP5
The NM_000263.4(NAGLU):c.461T>C(p.Ile154Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,614,098 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I154V) has been classified as Uncertain significance.
Frequency
Consequence
NM_000263.4 missense
Scores
Clinical Significance
Conservation
Publications
- mucopolysaccharidosis type 3BInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Orphanet, Myriad Women’s Health
- Charcot-Marie-Tooth disease axonal type 2VInheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Pathogenic. The variant received 11 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| NAGLU | NM_000263.4 | c.461T>C | p.Ile154Thr | missense_variant | Exon 2 of 6 | ENST00000225927.7 | NP_000254.2 | |
| NAGLU | XM_024450771.2 | c.518T>C | p.Ile173Thr | missense_variant | Exon 3 of 7 | XP_024306539.1 | ||
| NAGLU | XM_047436138.1 | c.-79+820T>C | intron_variant | Intron 1 of 4 | XP_047292094.1 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152220Hom.: 0 Cov.: 35 show subpopulations
GnomAD2 exomes AF: 0.00000398 AC: 1AN: 251392 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 0.00000137 AC: 2AN: 1461878Hom.: 0 Cov.: 58 AF XY: 0.00 AC XY: 0AN XY: 727244 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152220Hom.: 0 Cov.: 35 AF XY: 0.0000134 AC XY: 1AN XY: 74362 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Mucopolysaccharidosis, MPS-III-B;C5569050:Charcot-Marie-Tooth disease axonal type 2V Pathogenic:1
This variant disrupts the p.Ile154 amino acid residue in NAGLU. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11836372, 29979746). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Experimental studies have shown that this missense change affects NAGLU function (PMID: 29979746). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt NAGLU protein function. ClinVar contains an entry for this variant (Variation ID: 2503909). This variant has not been reported in the literature in individuals affected with NAGLU-related conditions. This variant is present in population databases (rs770684838, gnomAD 0.006%). This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 154 of the NAGLU protein (p.Ile154Thr). -
not specified Uncertain:1
Variant summary: NAGLU c.461T>C (p.Ile154Thr) results in a non-conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 4e-06 in 251392 control chromosomes. To our knowledge, no occurrence of c.461T>C in individuals affected with Mucopolysaccharidosis Type IIIB (Sanfilippo Syndrome B) has been reported. At least one publication reports experimental evidence evaluating an impact on protein function in vitro. The most pronounced variant effect results in 10%-<30% of normal activity (Clark_2018). The following publications have been ascertained in the context of this evaluation (PMID: 31342580, 29979746, 28102005). ClinVar contains an entry for this variant (Variation ID: 2503909). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at