rs746612719

Positions:

• chr1-241512025-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 6P and 4B. PM1 PP3_Strong BS2

The NM_000143.4(FH):​c.497G>A​(p.Gly166Glu) variant causes a missense change. The variant allele was found at a frequency of 0.00000547 in 1,461,696 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. G166R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: FH NM_000143.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.16

Genes affected

FH (HGNC:3700): (fumarate hydratase) The protein encoded by this gene is an enzymatic component of the tricarboxylic acid (TCA) cycle, or Krebs cycle, and catalyzes the formation of L-malate from fumarate. It exists in both a cytosolic form and an N-terminal extended form, differing only in the translation start site used. The N-terminal extended form is targeted to the mitochondrion, where the removal of the extension generates the same form as in the cytoplasm. It is similar to some thermostable class II fumarases and functions as a homotetramer. Mutations in this gene can cause fumarase deficiency and lead to progressive encephalopathy. [provided by RefSeq, Jul 2008]

FH (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 14 uncertain in NM_000143.4
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985
• BS2: High AC in GnomAdExome4 at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FH	NM_000143.4	c.497G>A	p.Gly166Glu	missense_variant	4/10	ENST00000366560.4	NP_000134.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FH	ENST00000366560.4	c.497G>A	p.Gly166Glu	missense_variant	4/10	1	NM_000143.4	ENSP00000355518.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461696 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727144

Gnomad4 AFR exome AF: 0.00

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: 0.00000719

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

TwinsUK AF: 0.00 AC: 0

ALSPAC AF: 0.000259 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 18, 2021

This sequence change replaces glycine with glutamic acid at codon 166 of the FH protein (p.Gly166Glu). The glycine residue is highly conserved and there is a moderate physicochemical difference between glycine and glutamic acid. This variant is not present in population databases (ExAC no frequency). This missense change has been observed in individual(s) with pheochromocytoma (PMID: 30877234). ClinVar contains an entry for this variant (Variation ID: 566616). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt FH protein function. 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	0.60
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.80	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	3.9	H
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-7.4	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.88
MutPred		0.87		Gain of disorder (P = 0.0847);
MVP		0.99
MPC		1.1
ClinPred		1.0	D
GERP RS		4.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.96
gMVP		0.95

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: rs746612719; hg19: chr1-241675325; COSMIC: COSV105921159; COSMIC: COSV105921159;