6-109743207-G-C

Position:

• chr6-109743207-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_014845.6(FIG4):​c.974G>C​(p.Arg325Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000197 in 152,146 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.000020 (0 hom., cov: 32)
• Consequence: FIG4 NM_014845.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.24

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]

FIG4 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FIG4	NM_014845.6	c.974G>C	p.Arg325Thr	missense_variant	9/23	ENST00000230124.8	NP_055660.1
FIG4	XM_011536281.4	c.911G>C	p.Arg304Thr	missense_variant	9/23		XP_011534583.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FIG4	ENST00000230124.8	c.974G>C	p.Arg325Thr	missense_variant	9/23	1	NM_014845.6	ENSP00000230124.4

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152146 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000197

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152146 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74326

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000197

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000189

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

Aug 16, 2022

This sequence change replaces arginine, which is basic and polar, with threonine, which is neutral and polar, at codon 325 of the FIG4 protein (p.Arg325Thr). 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: 407083). 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: "Probably Damaging"; Align-GVGD: "Class C0"). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.27	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Pathogenic	4.0	H
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-5.5	D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0090	D
Polyphen		0.97	D
Vest4		0.98
MutPred		0.95		Loss of methylation at R325 (P = 0.049);
MVP		0.89
MPC		1.2
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.97
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1060501400; hg19: chr6-110064410;