rs774271810

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 5P and 2B. PM1PM2PP2BP4_Moderate

The NM_005677.4(COLQ):​c.164C>T​(p.Thr55Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000291 in 1,614,078 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. 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. T55A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

COLQ
NM_005677.4 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: -0.170

Publications

1 publications found
Variant links:
Genes affected
COLQ (HGNC:2226): (collagen like tail subunit of asymmetric acetylcholinesterase) This gene encodes the subunit of a collagen-like molecule associated with acetylcholinesterase in skeletal muscle. Each molecule is composed of three identical subunits. Each subunit contains a proline-rich attachment domain (PRAD) that binds an acetylcholinesterase tetramer to anchor the catalytic subunit of the enzyme to the basal lamina. Mutations in this gene are associated with endplate acetylcholinesterase deficiency. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]
COLQ Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 5
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, PanelApp Australia

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_005677.4
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 16 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Gene score misZ: -0.21928 (below the threshold of 3.09). Trascript score misZ: -0.17745 (below the threshold of 3.09). GenCC associations: The gene is linked to congenital myasthenic syndrome 5.
BP4
Computational evidence support a benign effect (MetaRNN=0.15610576).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COLQNM_005677.4 linkc.164C>T p.Thr55Met missense_variant Exon 2 of 17 ENST00000383788.10 NP_005668.2 Q9Y215-1
COLQNM_080538.2 linkc.134C>T p.Thr45Met missense_variant Exon 2 of 17 NP_536799.1 Q9Y215-2
COLQNM_080539.4 linkc.164C>T p.Thr55Met missense_variant Exon 2 of 16 NP_536800.2 Q9Y215-3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COLQENST00000383788.10 linkc.164C>T p.Thr55Met missense_variant Exon 2 of 17 1 NM_005677.4 ENSP00000373298.3 Q9Y215-1
COLQENST00000603808.5 linkc.164C>T p.Thr55Met missense_variant Exon 2 of 17 1 ENSP00000474271.1 A0A0C4DGS2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152198
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
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:
0.0000398
AC:
10
AN:
251418
AF XY:
0.0000589
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:
0.0000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000287
AC:
42
AN:
1461880
Hom.:
0
Cov.:
31
AF XY:
0.0000316
AC XY:
23
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000351
AC:
39
AN:
1112010
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000329
AC:
5
AN:
152198
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74338
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.455
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.000139
Hom.:
0
Bravo
AF:
0.0000227
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Congenital myasthenic syndrome 5 Uncertain:1
Apr 12, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 55 of the COLQ protein (p.Thr55Met). This variant is present in population databases (rs774271810, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with COLQ-related conditions. ClinVar contains an entry for this variant (Variation ID: 536240). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The methionine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Inborn genetic diseases Uncertain:1
Mar 28, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.164C>T (p.T55M) alteration is located in exon 2 (coding exon 2) of the COLQ gene. This alteration results from a C to T substitution at nucleotide position 164, causing the threonine (T) at amino acid position 55 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.076
BayesDel_addAF
Benign
-0.17
T
BayesDel_noAF
Benign
-0.28
CADD
Benign
12
DANN
Benign
0.70
DEOGEN2
Benign
0.41
T;.;.;.;.
Eigen
Benign
-0.64
Eigen_PC
Benign
-0.58
FATHMM_MKL
Benign
0.076
N
LIST_S2
Benign
0.76
T;T;T;T;T
M_CAP
Uncertain
0.15
D
MetaRNN
Benign
0.16
T;T;T;T;T
MetaSVM
Benign
-0.45
T
MutationAssessor
Benign
1.9
L;.;.;L;.
PhyloP100
-0.17
PrimateAI
Benign
0.39
T
PROVEAN
Benign
-1.0
N;N;.;N;.
REVEL
Benign
0.22
Sift
Benign
0.086
T;T;.;.;.
Sift4G
Benign
0.088
T;T;T;T;T
Polyphen
0.015
B;B;.;B;.
Vest4
0.25
MutPred
0.25
Loss of glycosylation at T55 (P = 0.0098);.;Loss of glycosylation at T55 (P = 0.0098);Loss of glycosylation at T55 (P = 0.0098);.;
MVP
0.87
MPC
0.24
ClinPred
0.066
T
GERP RS
3.5
Varity_R
0.11
gMVP
0.38
Mutation Taster
=87/13
polymorphism

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: rs774271810; hg19: chr3-15531087; COSMIC: COSV67525355; API