rs121908141

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM5

The NM_174878.3(CLRN1):​c.359T>C​(p.Met120Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000867 in 1,613,998 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M120K) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

CLRN1
NM_174878.3 missense

Scores

1
8
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.92

Publications

6 publications found
Variant links:
Genes affected
CLRN1 (HGNC:12605): (clarin 1) This gene encodes a protein that contains a cytosolic N-terminus, multiple helical transmembrane domains, and an endoplasmic reticulum membrane retention signal, TKGH, in the C-terminus. The encoded protein may be important in development and homeostasis of the inner ear and retina. Mutations within this gene have been associated with Usher syndrome type IIIa. Multiple transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]
SIAH2-AS1 (HGNC:40526): (SIAH2 antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-150941656-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 4393.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLRN1NM_174878.3 linkc.359T>C p.Met120Thr missense_variant Exon 2 of 3 ENST00000327047.6 NP_777367.1 P58418-3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CLRN1ENST00000327047.6 linkc.359T>C p.Met120Thr missense_variant Exon 2 of 3 1 NM_174878.3 ENSP00000322280.1 P58418-3
ENSG00000260234ENST00000569170.5 linkn.86T>C non_coding_transcript_exon_variant Exon 1 of 11 1 ENSP00000457784.1 H3BUT2

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152206
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251344
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461792
Hom.:
0
Cov.:
31
AF XY:
0.00000550
AC XY:
4
AN XY:
727194
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000809
AC:
9
AN:
1111944
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74368
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41468
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.408
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00112
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
May 09, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: CLRN1 c.359T>C (p.Met120Thr) 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 are either unavailable or do not agree on the potential impact of this missense change. The variant allele was found at a frequency of 8e-06 in 251344 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.359T>C in individuals affected with Usher Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. A different variant affecting the same codon has been classified as likely pathogenic (c.359T>A (p.Met120Lys)), supporting the critical relevance of codon 120 to CLRN1 protein function. ClinVar contains an entry for this variant (Variation ID: 1969574). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Usher syndrome type 3 Uncertain:1
May 29, 2025
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Uncertain:1
Jan 28, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 120 of the CLRN1 protein (p.Met120Thr). This variant is present in population databases (rs121908141, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with CLRN1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant disrupts the p.Met120 amino acid residue in CLRN1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11524702, 19753315). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Benign
-0.062
T
BayesDel_noAF
Uncertain
-0.020
CADD
Benign
22
DANN
Benign
0.94
DEOGEN2
Benign
0.35
.;T;.
Eigen
Uncertain
0.39
Eigen_PC
Uncertain
0.47
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.70
T;T;T
M_CAP
Benign
0.044
D
MetaRNN
Uncertain
0.69
D;D;D
MetaSVM
Benign
-0.32
T
PhyloP100
7.9
PrimateAI
Uncertain
0.64
T
PROVEAN
Benign
-2.2
N;N;N
REVEL
Uncertain
0.51
Sift
Uncertain
0.017
D;D;D
Sift4G
Uncertain
0.0080
D;D;D
Polyphen
0.74
P;P;.
Vest4
0.84
MutPred
0.27
.;Loss of stability (P = 0.085);Loss of stability (P = 0.085);
MVP
0.75
MPC
0.060
ClinPred
0.93
D
GERP RS
5.1
Varity_R
0.43
gMVP
0.79
Mutation Taster
=33/67
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs121908141; hg19: chr3-150659443; COSMIC: COSV99902368; COSMIC: COSV99902368; API