chr6-98874394-A-G

Variant names:

• chr6-98874394-A-G
• rs1554215804
• NM_001278716.2:c.1750T>C

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1 PM2 PP2 PP3_Strong PP5_Moderate

The NM_001278716.2(FBXL4):​c.1750T>C​(p.Cys584Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C584F) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: FBXL4 NM_001278716.2 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.95
• Publications: 2 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001278716.2
• 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 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.968
• PP5: Variant 6-98874394-A-G is Pathogenic according to our data. Variant chr6-98874394-A-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 437484.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBXL4	NM_001278716.2	c.1750T>C	p.Cys584Arg	missense_variant	Exon 10 of 10	ENST00000369244.7	NP_001265645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBXL4	ENST00000369244.7	c.1750T>C	p.Cys584Arg	missense_variant	Exon 10 of 10	1	NM_001278716.2	ENSP00000358247.1
FBXL4	ENST00000229971.2	c.1750T>C	p.Cys584Arg	missense_variant	Exon 9 of 9	1		ENSP00000229971.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Mitochondrial DNA depletion syndrome 13 Pathogenic:1

Aug 10, 2017

Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The NM_012160.4:c.1750T>C (NP_036292.2:p.Cys584Arg) [GRCH38: NC_000006.12:g.98874394A>G] variant in FBXL4 gene is interpretated to be a Likely Pathogenic 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. PP2:This is a missense variant in FBXL4 with a low rate of benign and high rate of pathogenic missense variations. PP3:Computational evidence/predictors indicate the variant has deleterious effect on FBXL4 structure, function, or protein-protein interaction. PP4:Patient’s phenotype or family history is highly specific for FBXL4. PP5:Reputable source(s) suggest that the variant is pathogenic. Based on this evidence code ClinGen Pathogenicity Calculator (PMID:28081714) suggested that the variant is Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Benign	0.39	T;T
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.86	.;D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Benign	-0.69	T
MutationAssessor	Pathogenic	3.4	M;M
PhyloP100		8.9
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-9.4	D;D
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0020	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.89
MutPred		0.86		Gain of disorder (P = 0.0067);Gain of disorder (P = 0.0067);
MVP		0.64
MPC		0.51
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.96
gMVP		0.93
Mutation Taster		=0/100	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1554215804; hg19: chr6-99322270;