rs1554218789

Positions:

• chr6-98899268-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP3 PP5_Moderate

The NM_001278716.2(FBXL4):​c.1317G>A​(p.Glu439=) variant causes a splice region, synonymous change. The variant allele was found at a frequency of 0.000000684 in 1,461,336 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: FBXL4 NM_001278716.2 splice_region, synonymous
• Scores: Splicing: ADA: 0.9984
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.77

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 6-98899268-C-T is Pathogenic according to our data. Variant chr6-98899268-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 437503.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr6-98899268-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FBXL4	NM_001278716.2	c.1317G>A	p.Glu439=	splice_region_variant, synonymous_variant	7/10	ENST00000369244.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FBXL4	ENST00000369244.7	c.1317G>A	p.Glu439=	splice_region_variant, synonymous_variant	7/10	1	NM_001278716.2	P1
FBXL4	ENST00000229971.2	c.1317G>A	p.Glu439=	splice_region_variant, synonymous_variant	6/9	1		P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461336 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726948

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Mitochondrial DNA depletion syndrome 13 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Aug 10, 2017

The NM_012160.4:c.1317G>A (NP_036292.2:p.Glu439=) [GRCH38: NC_000006.12:g.98899268C>T] variant in FBXL4 gene is interpretated to be a Pathogenic based on ACMG guidelines (PMID: 25741868). This variant meets one or more of the following evidence codes reported in the ACMG-guideline. PVS1:This variant is a predcted null variant in FBXL4 where loss of function is a known mechanism of disease. PM2:This variant is absent in key population databases. 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 Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.22
CADD	Benign	20
DANN	Benign	0.94

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
SpliceAI score (max)		0.93		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.93		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554218789; hg19: chr6-99347144;