rs146638016

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 1P and 3B. PP2BP4_ModerateBS1_Supporting

The NM_001278716.2(FBXL4):​c.1388T>C​(p.Met463Thr) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000735 in 1,613,440 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/24 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. M463V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00045 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00076 ( 1 hom. )

Consequence

FBXL4
NM_001278716.2 missense, splice_region

Scores

1
3
15
Splicing: ADA: 0.001041
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.41

Publications

2 publications found
Variant links:
Genes affected
FBXL4 (HGNC:13601): (F-box and leucine rich repeat protein 4) This gene encodes a member of the F-box protein family, which are characterized by an approximately 40 amino acid motif, the F-box. F-box proteins constitute one subunit of modular E3 ubiquitin ligase complexes, called SCF complexes, which function in phosphorylation-dependent ubiquitination. The F-box domain mediates protein-protein interactions and binds directly to S-phase kinase-associated protein 1. In addition to an F-box domain, the encoded protein contains at least 9 tandem leucine-rich repeats. The ubiquitin ligase complex containing the encoded protein may function in cell-cycle control by regulating levels of lysine-specific demethylase 4A. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]
FBXL4 Gene-Disease associations (from GenCC):
  • Leigh syndrome
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • mitochondrial DNA depletion syndrome 13
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 24 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 0.55467 (below the threshold of 3.09). Trascript score misZ: 1.2845 (below the threshold of 3.09). GenCC associations: The gene is linked to Leigh syndrome, mitochondrial DNA depletion syndrome 13.
BP4
Computational evidence support a benign effect (MetaRNN=0.23837957).
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.000764 (1117/1461220) while in subpopulation NFE AF = 0.00095 (1056/1111526). AF 95% confidence interval is 0.000902. There are 1 homozygotes in GnomAdExome4. There are 541 alleles in the male GnomAdExome4 subpopulation. Median coverage is 30. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBXL4NM_001278716.2 linkc.1388T>C p.Met463Thr missense_variant, splice_region_variant Exon 8 of 10 ENST00000369244.7 NP_001265645.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBXL4ENST00000369244.7 linkc.1388T>C p.Met463Thr missense_variant, splice_region_variant Exon 8 of 10 1 NM_001278716.2 ENSP00000358247.1
FBXL4ENST00000229971.2 linkc.1388T>C p.Met463Thr missense_variant, splice_region_variant Exon 7 of 9 1 ENSP00000229971.1

Frequencies

GnomAD3 genomes
AF:
0.000453
AC:
69
AN:
152220
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000941
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000867
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000331
AC:
83
AN:
251030
AF XY:
0.000332
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000463
Gnomad NFE exome
AF:
0.000626
Gnomad OTH exome
AF:
0.000654
GnomAD4 exome
AF:
0.000764
AC:
1117
AN:
1461220
Hom.:
1
Cov.:
30
AF XY:
0.000744
AC XY:
541
AN XY:
726944
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33462
American (AMR)
AF:
0.000134
AC:
6
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39668
South Asian (SAS)
AF:
0.000116
AC:
10
AN:
86254
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53350
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5764
European-Non Finnish (NFE)
AF:
0.000950
AC:
1056
AN:
1111526
Other (OTH)
AF:
0.000712
AC:
43
AN:
60358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
52
105
157
210
262
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
44
88
132
176
220
<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:
0.000453
AC:
69
AN:
152220
Hom.:
0
Cov.:
32
AF XY:
0.000430
AC XY:
32
AN XY:
74356
show subpopulations
African (AFR)
AF:
0.000169
AC:
7
AN:
41462
American (AMR)
AF:
0.0000654
AC:
1
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.0000941
AC:
1
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000867
AC:
59
AN:
68046
Other (OTH)
AF:
0.000478
AC:
1
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.000644
Hom.:
0
Bravo
AF:
0.000461
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00130
AC:
5
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000930
AC:
8
ExAC
AF:
0.000362
AC:
44
EpiCase
AF:
0.000600
EpiControl
AF:
0.000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:3
Jan 23, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BP4 -

Mar 04, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Reported in an individual with generalized dystonia, speech impairment and dysphagia who also harbored a second variant in the FBXL4 gene, however it is unknown whether the variants occurred on the same (in cis) or opposite (in trans) chromosomes (Kumar et al., 2019); This variant is associated with the following publications: (PMID: 31731261) -

Aug 02, 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 463 of the FBXL4 protein (p.Met463Thr). This variant is present in population databases (rs146638016, gnomAD 0.06%). This variant has not been reported in the literature in individuals affected with FBXL4-related conditions. ClinVar contains an entry for this variant (Variation ID: 437744). 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: "Benign"; Align-GVGD: "Class C25"). 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. -

Mitochondrial DNA depletion syndrome 13 Uncertain:2
Aug 10, 2017
Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:reference population

The NM_012160.4:c.1388T>C (NP_036292.2:p.Met463Thr) [GRCH38: NC_000006.12:g.98880554A>G] variant in FBXL4 gene is interpretated to be a Uncertain Significance - Conflicting Evidence based on ACMG guidelines (PMID: 25741868). This variant meets one or more of the following evidence codes reported in the ACMG-guideline. PM2:This variant is absent in key population databases. BP4:Computational evidence/predictors indicate no impact on the FBXL4 structure, function, or protein-protein interaction. Based on this evidence code ClinGen Pathogenicity Calculator (PMID:28081714) suggested that the variant is Uncertain Significance - Conflicting Evidence. -

Jul 27, 2022
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.35
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
19
DANN
Benign
0.87
DEOGEN2
Benign
0.044
T;T
Eigen
Benign
0.078
Eigen_PC
Uncertain
0.24
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Benign
0.79
.;T
M_CAP
Benign
0.037
D
MetaRNN
Benign
0.24
T;T
MetaSVM
Benign
-0.60
T
MutationAssessor
Benign
-0.015
N;N
PhyloP100
5.4
PrimateAI
Pathogenic
0.84
D
PROVEAN
Benign
-0.81
N;N
REVEL
Benign
0.17
Sift
Benign
0.59
T;T
Sift4G
Benign
0.095
T;T
Polyphen
0.63
P;P
Vest4
0.69
MVP
0.32
MPC
0.073
ClinPred
0.049
T
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.29
gMVP
0.53
Mutation Taster
=70/30
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.0010
dbscSNV1_RF
Benign
0.076
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: rs146638016; hg19: chr6-99328430; API