rs142783718

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4

The NM_001079802.2(FKTN):​c.374G>A​(p.Gly125Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,612,224 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 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. G125A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000017 ( 0 hom. )

Consequence

FKTN
NM_001079802.2 missense

Scores

5
14

Clinical Significance

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

Conservation

PhyloP100: 1.78

Publications

4 publications found
Variant links:
Genes affected
FKTN (HGNC:3622): (fukutin) The protein encoded by this gene is a putative transmembrane protein that is localized to the cis-Golgi compartment, where it may be involved in the glycosylation of alpha-dystroglycan in skeletal muscle. The encoded protein is thought to be a glycosyltransferase and could play a role in brain development. Defects in this gene are a cause of Fukuyama-type congenital muscular dystrophy (FCMD), Walker-Warburg syndrome (WWS), limb-girdle muscular dystrophy type 2M (LGMD2M), and dilated cardiomyopathy type 1X (CMD1X). Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Nov 2010]
FKTN Gene-Disease associations (from GenCC):
  • autosomal recessive limb-girdle muscular dystrophy type 2M
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 4
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • myopathy caused by variation in FKTN
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital muscular dystrophy without intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscle-eye-brain disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscular dystrophy-dystroglycanopathy, type A
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • dilated cardiomyopathy 1X
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.29602242).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKTNNM_001079802.2 linkc.374G>A p.Gly125Asp missense_variant Exon 6 of 11 ENST00000357998.10 NP_001073270.1 O75072-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FKTNENST00000357998.10 linkc.374G>A p.Gly125Asp missense_variant Exon 6 of 11 5 NM_001079802.2 ENSP00000350687.6 O75072-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152180
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
249624
AF XY:
0.0000222
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:
0.0000268
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000171
AC:
25
AN:
1460044
Hom.:
0
Cov.:
32
AF XY:
0.0000220
AC XY:
16
AN XY:
726350
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33424
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86176
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4304
European-Non Finnish (NFE)
AF:
0.0000225
AC:
25
AN:
1111952
Other (OTH)
AF:
0.00
AC:
0
AN:
60228
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
3
5
8
10
13
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:
0.0000131
AC:
2
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

Walker-Warburg congenital muscular dystrophy Uncertain:2
Jul 27, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 125 of the FKTN protein (p.Gly125Asp). This variant is present in population databases (rs142783718, gnomAD 0.003%). This missense change has been observed in individual(s) with autosomal recessive dilated cardiomyopathy (Invitae). ClinVar contains an entry for this variant (Variation ID: 850972). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -

Mar 11, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Mar 05, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.G125D variant (also known as c.374G>A), located in coding exon 4 of the FKTN gene, results from a G to A substitution at nucleotide position 374. The glycine at codon 125 is replaced by aspartic acid, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.086
BayesDel_addAF
Uncertain
0.034
T
BayesDel_noAF
Benign
-0.13
CADD
Benign
18
DANN
Uncertain
1.0
DEOGEN2
Benign
0.13
T;T;.;.
Eigen
Benign
-0.14
Eigen_PC
Benign
-0.079
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.81
.;T;.;T
M_CAP
Benign
0.083
D
MetaRNN
Benign
0.30
T;T;T;T
MetaSVM
Uncertain
0.22
D
MutationAssessor
Benign
1.9
L;L;L;L
PhyloP100
1.8
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-0.35
.;N;N;N
REVEL
Uncertain
0.35
Sift
Benign
0.19
.;T;T;T
Sift4G
Benign
0.38
T;T;T;T
Polyphen
0.017
B;B;.;.
Vest4
0.41
MutPred
0.49
Gain of helix (P = 0.0128);Gain of helix (P = 0.0128);Gain of helix (P = 0.0128);Gain of helix (P = 0.0128);
MVP
0.89
MPC
0.11
ClinPred
0.25
T
GERP RS
1.7
Varity_R
0.060
gMVP
0.73
Mutation Taster
=80/20
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs142783718; hg19: chr9-108366500; COSMIC: COSV99795546; API