rs863224004

Positions:

• chr1-241504053-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000143.4(FH):​c.1097G>A​(p.Ser366Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 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 Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. S366S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: FH NM_000143.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 7.37

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]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000143.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.948
• PP5: Variant 1-241504053-C-T is Pathogenic according to our data. Variant chr1-241504053-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 214419.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FH	NM_000143.4	c.1097G>A	p.Ser366Asn	missense_variant	7/10	ENST00000366560.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FH	ENST00000366560.4	c.1097G>A	p.Ser366Asn	missense_variant	7/10	1	NM_000143.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461696 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727136

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jul 26, 2023	The FH c.1097G>A (p.Ser366Asn) variant has been reported in the published literature in individuals with phenotypes associated with hereditary leiomyomatosis and renal cell cancer (HLRCC)(PMID: 12772087 (2003), 16237213 (2005), 21630274 (2011), 31299266 (2019)). Immunohistochemical analysis of tumors from patients with this variant showed loss of heterozygosity and were positive for (2-succinyl) cysteine (2SC) (termed protein succination) due to deficient fumarase (PMID: 21630274 (2011)). Additionally, this variant is predicted to alter the active site of the FH protein (PMID: 21445611 (2011), 12761039 (2003)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is damaging. Based on the available information, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jul 27, 2022	Not observed at significant frequency in large population cohorts (gnomAD); Also known as FH c.968G>A, p.Ser323Asn; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 15937070, 12761039, 31299266, 18366737, 21630274, 12772087, 16597677, 16029320, 16237213, 21445611, 33237286) -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Dec 31, 2023	This sequence change replaces serine, which is neutral and polar, with asparagine, which is neutral and polar, at codon 366 of the FH protein (p.Ser366Asn). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with multiple cutaneous and uterine leiomyomatosis (MCUL) or hereditary leiomyomatosis and renal cell cancer (HLRCC) (PMID: 12761039, 12772087, 16237213; Invitae). This variant is also known as G968A or S323N. ClinVar contains an entry for this variant (Variation ID: 214419). 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 with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Hereditary leiomyomatosis and renal cell cancer Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Jan 17, 2023	This variant is considered likely pathogenic. This variant has been reported in multiple individuals with clinical features of gene-specific disease [PMID: 12761039, 31299266, 31831373, 21630274, 12772087]. -
Likely pathogenic, criteria provided, single submitter	clinical testing	St. Jude Molecular Pathology, St. Jude Children's Research Hospital	Oct 03, 2022	The FH c.1097G>A (p.Ser366Asn) missense change is absent in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). This variant has been identified in multiple individuals with leiomyomas and/or renal cell carcinoma (PMID: 12761039, 12772087, 21630274). The tumors of at least three of these individuals also demonstrated loss of heterozygosity (PMID: 12761039, 21630274). In addition, immunohistochemical analysis of tumors from patients with this germline variant have shown an accumulation of succinated proteins as a result of fumarase deficiency (PMID: 21630274). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant is also known as p.Ser323Asn in the literature. In summary, this variant meets criteria to be classified as likely pathogenic. -

Fumarase deficiency Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Dec 22, 2023

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

May 23, 2023

The p.S366N pathogenic mutation (also known as c.1097G>A), located in coding exon 7 of the FH gene, results from a G to A substitution at nucleotide position 1097. The serine at codon 366 is replaced by asparagine, an amino acid with highly similar properties. This alteration has been reported in numerous individuals with multiple cutaneous and uterine leiyomyomatosis (Alam NA et al. J Mol Diagn. 2005 Oct;7:437-43; Toro JR et al. Am. J. Hum. Genet. 2003 Jul;73:95-106; Bardella C et al. J. Pathol. 2011 Sep;225(1):4-11; Gupta S et al. Hum Pathol, 2019 Sep;91:114-122; Ambry internal data). Immunohistochemical analysis of tumors in patients with the germline p.S366N mutation have shown that this alteration results in an accumulation of succinated proteins as a result of deficient fumarase; these patients' tumors also demonstrated loss of heterozygosity (Bardella C et al. J. Pathol. 2011 Sep;225(1):4-11). In addition, the p.S366N variant has been predicted to alter the enzymatic active site of the FH protein (Picaud S et al. J. Inherit. Metab. Dis. 2011 Jun;34:671-6; Alam NA et al. Hum. Mol. Genet. 2003 Jun;12:1241-52). Based on internal structural analysis, this variant is anticipated to disrupt a region of known function (Ajalla Aleixo MA et al. FEBS J. 2019 May;286:1925-1940; Mechaly AE et al. FEBS Lett. 2012 Jun;586:1606-11). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Of note, this alteration is also designated as S323N (c.968G>A) in some published literature. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.83	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	5.1	H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.0	D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MutPred		0.70		Loss of phosphorylation at S366 (P = 0.0501);
MVP		0.98
MPC		0.90
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.98
gMVP		0.98

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: rs863224004; hg19: chr1-241667353;