6-109789595-G-T

Position:

• chr6-109789595-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_014845.6(FIG4):​c.2098G>T​(p.Asp700Tyr) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: FIG4 NM_014845.6 missense, splice_region
• Scores: Splicing: ADA: 0.9801
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.36

Genes affected

FIG4 (HGNC:16873): (FIG4 phosphoinositide 5-phosphatase) The protein encoded by this gene belongs to the SAC domain-containing protein gene family. The SAC domain, approximately 400 amino acids in length and consisting of seven conserved motifs, has been shown to possess phosphoinositide phosphatase activity. The yeast homolog, Sac1p, is involved in the regulation of various phosphoinositides, and affects diverse cellular functions such as actin cytoskeleton organization, Golgi function, and maintenance of vacuole morphology. Membrane-bound phosphoinositides function as signaling molecules and play a key role in vesicle trafficking in eukaryotic cells. Mutations in this gene have been associated with Charcot-Marie-Tooth disease, type 4J. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 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. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FIG4	NM_014845.6	c.2098G>T	p.Asp700Tyr	missense_variant, splice_region_variant	19/23	ENST00000230124.8
FIG4	XM_011536281.4	c.2035G>T	p.Asp679Tyr	missense_variant, splice_region_variant	19/23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FIG4	ENST00000230124.8	c.2098G>T	p.Asp700Tyr	missense_variant, splice_region_variant	19/23	1	NM_014845.6	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 30, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with tyrosine, which is neutral and polar, at codon 700 of the FIG4 protein (p.Asp700Tyr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with FIG4-related conditions. ClinVar contains an entry for this variant (Variation ID: 543422). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.44
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Benign	0.29	T;.
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Benign	0.025	T
MetaRNN	Uncertain	0.51	D;D
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.66	T
PROVEAN	Uncertain	-3.5	D;D
REVEL	Uncertain	0.34
Sift	Uncertain	0.0070	D;D
Sift4G	Benign	0.13	T;D
Polyphen		1.0	D;.
Vest4		0.75
MutPred		0.41		Loss of disorder (P = 0.0135);.;
MVP		0.73
MPC		0.89
ClinPred		0.97	D
GERP RS		5.7
Varity_R		0.50
gMVP		0.66

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Pathogenic	0.80
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

LitVar

Other links and lift over

dbSNP: rs1554308483; hg19: chr6-110110798;