NM_000143.4:c.988A>G

Variant names:

• chr1-241504162-T-C
• rs776313200
• NM_000143.4:c.988A>G
• FH p.Thr330Ala

GermlineCancer (beta)

Variant summary

Our verdict is Uncertain significance.

+5 Uncertain · Hot

-7

-6

-1

0

+5

+6

+9

+10

BenignB

Likely BenignLB

UncertainVUS

Likely PathogenicLP

PathogenicP

The variant received 5 classification points (ACGS-UK Somatic Oncogenicity v2025). O3_SupportingO5_SupportingO6_SupportingO7_SupportingO8_Supporting

The NM_000143.4(FH):c.988A>G (p.Thr330Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The gene FH is a tumor suppressor gene (CancerMine: 5 TSG, 1 oncogene, 2 driver citations). The gene FH is a known oncogene (CancerMine: 5 TSG, 1 oncogene, 2 driver citations). The gene FH is a cancer driver gene (CancerMine: 5 TSG, 1 oncogene, 2 driver citations). The variant allele was found at a cumulative frequency of 0.0000294 (AC=43) in the gnomAD database across 1,461,862 control chromosomes (no homozygotes observed). The grpmax filtering allele frequency (95% CI) is 0.0000291. In-silico predictor (REVEL) classifies this variant as likely damaging/oncogenic. Splicing prediction tools (SpliceAI) predict no significant impact on normal splicing. The affected nucleotide is highly conserved across species (PhyloP 100-way vertebrate score: 7.48). Variant has been reported in ClinVar as Uncertain Significance (★★). A different missense at the same amino acid position has been reported as Pathogenic/Likely Pathogenic in ClinVar: p.T330P: Pathogenic/Likely_pathogenic (ClinVar VariationId 575043, 2 stars) Other variants at the same amino acid position have been reported in ClinVar (not pathogenic): p.T330I: Uncertain_significance (ClinVar VariationId 1437249, 1 star); p.T330S: Uncertain_significance (ClinVar VariationId 460384, 1 star); p.T330= (synonymous): Likely_benign (ClinVar VariationId 1561277, 2 stars); p.T330= (synonymous): Benign/Likely_benign (ClinVar VariationId 3230468, 2 stars)

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000029 (0 hom.)
• Consequence: FH NM_000143.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.48
• Publications: 3 publications found

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 Gene-Disease associations (from GenCC):

• hereditary leiomyomatosis and renal cell cancer

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Natera, G2P, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia, Genomics England PanelApp
• fumaric aciduria

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, PanelApp Australia, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics, Natera
• pheochromocytoma-paraganglioma

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• leiomyosarcoma

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary pheochromocytoma-paraganglioma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Classification according to ACGS-UK Somatic Oncogenicity v2025

Classification was made for transcript:

Our verdict: Uncertain_significance. The variant received 5 points.

Apply	Criterion Code & Title / Strength	Strength	Rationale / Clinical Context
	O3Absent or very rare in population		Very rare in gnomAD (popmax AF <0.01%) — O3 supporting; GnomAD effective popmax AF = 0.000029 — very rare (O3 supporting [+1])
	O5Same location/impact as known oncogenic		Different AA at same residue with oncogenic evidence (or germline P/LP in TSG), or same AA change SCI Tier II Potential — Supporting (O5); ClinVar same-AA oncogenic/T1: false | ClinVar same-AA SCI tier: — | CGI same-AA oncogenic: false | TSG: true | ClinVar same-AA germline P/LP: false | CIViC LOF: false | ClinVar diff-AA oncogenic: false | ClinVar diff-AA germline P/LP: true
	O6Computational evidence supports deleterious effect		Computational evidence supports a deleterious/oncogenic effect; Missense variant — primary computational scorer supports an oncogenic/deleterious effect
	O7Mutational hotspot or critical domain		Supporting: cancerhotspots.org hit, critical domain, or missense neighbourhood hotspot; No cancerhotspots.org hit at this position; UniProt domain: 0 pathogenic, 0 benign.; ±8 AA neighbourhood: 12 pathogenic, 1 benign (OR vs. background: 41.7); Variant does not impact splicing — splice-hotspot path not applicable
	O8Missense constraint in gene or region		Missense in gene/domain constrained for missense variation where missense is common disease mechanism (O8 supporting); Gene/disease mechanism: missense is a common mechanism of oncogenesis; gnomAD missense Z-score: 2.07 (threshold ≥3.09 for constraint); Domain-level constraint: variant is in a critically constrained functional domain (IS_AT_CRITICAL_DOMAIN)

Variant Effect in Transcripts

Automated classification analysis was done for transcript: NM_000143.4. You can select a different transcript below to see updated classification assignments.

RefSeq Transcripts

Sel.	Gene / Transcript	Tags	HGVSc / HGVSp	Effect	Exon rank	Protein / UniProt
	FH NM_000143.4	MANE Select	c.988A>G p.Thr330Ala	missense	Exon 7 of 10	Prot: NP_000134.2

FH NM_000143.4

MANE Select

HGVSc / HGVSpc.988A>Gp.Thr330Ala

Exon rankExon 7 of 10

missense

Prot: NP_000134.2

Ensembl Transcripts

Sel.	Gene / Transcript	Tags	HGVSc / HGVSp	Effect	Exon rank	Protein / UniProt
	FH ENST00000366560.4	TSL:1MANE Select	c.988A>G p.Thr330Ala	missense	Exon 7 of 10	Prot: ENSP00000355518.4 UniProt:
	FH ENST00000958409.1		c.985A>G p.Thr329Ala	missense	Exon 7 of 10	Prot: ENSP00000628468.1 UniProt:
	FH ENST00000932939.1		c.940A>G p.Thr314Ala	missense	Exon 7 of 10	Prot: ENSP00000602998.1 UniProt:

FH ENST00000366560.4

TSL:1MANE Select

HGVSc / HGVSpc.988A>Gp.Thr330Ala

Exon rankExon 7 of 10

missense

Prot: ENSP00000355518.4UniProt: P07954-1

FH ENST00000958409.1

HGVSc / HGVSpc.985A>Gp.Thr329Ala

Exon rankExon 7 of 10

missense

Prot: ENSP00000628468.1UniProt: A0ACI8UZJ7

FH ENST00000932939.1

HGVSc / HGVSpc.940A>Gp.Thr314Ala

Exon rankExon 7 of 10

missense

Prot: ENSP00000602998.1UniProt: A0ACI8TNT4

Frequencies

Allele frequencies (AF), counts (AC/AN), homozygotes and coverage

Common (AF > 0.05 / Hom > 5)

Rare (AF ≤ 0.0001 / Hom ≤ 1)

Source / population	AF	AC	Hom	AN	Coverage
Global population databases 4 sources Large-scale international reference populations
GnomAD3 genomes	AF:	AC:	Hom:	AN:	Cov:32
GnomAD2 exomes	AF: 0.0000119	AC:3	Hom:	AN:251276	Cov:
GnomAD4 exome	AF: 0.0000294	AC:43	Hom:0	AN:1461862	Cov:32
GnomAD4 genome	AF:	AC:	Hom:	AN:	Cov:32

Showing 4 sources

Case/control cohorts

Cohort	Cases			Controls
	AF	AC	AN	AF	AC	AN
BipEx(Bipolar disorder (including schizoaffective))	0.00	0	28420	0.0000347	1	28844
SCHEMA(Schizophrenia)	0.0000295	2	67780	0.00000752	1	133066

Showing 2 cohortsAllele count / allele number. AF is computed from the counts for ASC (not provided by the source).

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Hereditary cancer-predisposing syndrome (1)
-	1	-	not provided (1)

Computational Scores

Algorithm	Calibrated pred.	Score	Prediction
AlphaGenome AVI	Pathogenic	21
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.47
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Uncertain	0.25
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	0.99	D
FuncVEP CTI	Benign	0.0087
GPN-Star LLR	N/A	-5.7
GPN-Star score	N/A	5.7
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.54	D
MetaRNN	Pathogenic	0.87	D
MetaSVM	Pathogenic	1.1	D
Mutation Taster	N/A	2/98	disease causing
MutationAssessor	Benign	1.6	L
PhyloP100	Uncertain	7.5
popEVE	Benign	-3.1
PrimateAI	Uncertain	0.72	T
PROVEAN	Uncertain	-3.5	D
REVEL	Pathogenic	0.74
Sift	Benign	0.054	T
Sift4G	Benign	0.082	T
Varity_R	N/A	0.66
VESM-3B	Benign	-5.4

Showing 28 of 28 scores

Splicing Scores

Algorithm	Calibrated pred.	Score	Prediction
Pangolin (max)	Benign	0.0
SpliceAI score (max)	Benign	0.0	Details are displayed if max score is > 0.2

Showing 2 of 2 scores

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

MaveDB functional evidence

MaveDB is a public repository of laboratory assays that test the effect of thousands of variants at once — treat this as supporting research data and interpret it with great caution; it is not a clinical classification.

No MaveDB functional evidence found for this variant.

Other links and lift over

dbSNP: rs776313200;

hg19: chr1-241667462;

ACMG debug oncogenicity

ACGS debug oncogenicity

ACMG debug germline

Submit to ClinVar