3-100713746-A-T

Variant summary

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

The NM_006070.6(TFG):c.61A>T(p.Ile21Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,459,162 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I21V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TFG NM_006070.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.66

Genes affected

TFG (HGNC:11758): (trafficking from ER to golgi regulator) There are several documented fusion oncoproteins encoded partially by this gene. This gene also participates in several oncogenic rearrangements resulting in anaplastic lymphoma and mixoid chondrosarcoma, and may play a role in the NF-kappaB pathway. Multiple transcript variants have been found for this gene. [provided by RefSeq, Sep 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.811

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TFG	NM_006070.6	c.61A>T	p.Ile21Phe	missense_variant	2/8	ENST00000240851.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TFG	ENST00000240851.9	c.61A>T	p.Ile21Phe	missense_variant	2/8	1	NM_006070.6	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250748 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135490

Gnomad AFR exome AF: 0.0000616

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1459162 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 725874

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 12, 2024

The c.61A>T (p.I21F) alteration is located in exon 2 (coding exon 1) of the TFG gene. This alteration results from a A to T substitution at nucleotide position 61, causing the isoleucine (I) at amino acid position 21 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary motor and sensory neuropathy, Okinawa type;C3714897:Hereditary spastic paraplegia 57 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 11, 2020

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. 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 C15"). This variant has not been reported in the literature in individuals with TFG-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces isoleucine with phenylalanine at codon 21 of the TFG protein (p.Ile21Phe). The isoleucine residue is highly conserved and there is a small physicochemical difference between isoleucine and phenylalanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Pathogenic	0.21
Cadd	Pathogenic	28
Dann	Uncertain	0.99
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Benign	0.054	D
MetaRNN	Pathogenic	0.81	D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.29	T
MutationAssessor	Pathogenic	2.9	M;M;M;M;.;M;.;.;M
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.86	D
Sift4G	Uncertain	0.0030	D;D;D;D;D;D;D;D;D
Polyphen		1.0	.;.;D;D;.;.;.;.;.
Vest4		0.86
MutPred		0.59		Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);Gain of catalytic residue at Q16 (P = 0.0787);
MVP		0.75
MPC		1.5
ClinPred		0.94	D
GERP RS		5.9
Varity_R		0.69
gMVP		0.74

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

Publications

LitVar

Other links and lift over

dbSNP: rs377136610; hg19: chr3-100432590;