rs1060500901
Positions:
Variant summary
Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PVS1_StrongPM2PP3PP5_Very_Strong
The NM_000143.4(FH):c.738+2T>C variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).
Frequency
Genomes: not found (cov: 32)
Consequence
FH
NM_000143.4 splice_donor
NM_000143.4 splice_donor
Scores
5
1
1
Splicing: ADA: 0.9906
1
1
Clinical Significance
Conservation
PhyloP100: 7.64
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]
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ACMG classification
Classification made for transcript
Verdict is Pathogenic. Variant got 15 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.11872146 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, max_spliceai. No scorers claiming Uncertain. Scorers claiming Benign: dbscSNV1_RF.
PP5
Variant 1-241508601-A-G is Pathogenic according to our data. Variant chr1-241508601-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 405921.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.738+2T>C | splice_donor_variant | ENST00000366560.4 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|
FH | ENST00000366560.4 | c.738+2T>C | splice_donor_variant | 1 | NM_000143.4 | P1 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD3 genomes
Cov.:
32
GnomAD4 exome Cov.: 31
GnomAD4 exome
Cov.:
31
GnomAD4 genome Cov.: 32
GnomAD4 genome
Cov.:
32
ClinVar
Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link
Submissions by phenotype
not provided Pathogenic:2
Pathogenic, criteria provided, single submitter | clinical testing | Invitae | Jun 20, 2023 | For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 405921). Disruption of this splice site has been observed in individuals with multiple cutaneous leiomyomas and/or renal cell carcinoma (PMID: 26173633, 28300276; Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 5 of the FH gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in FH are known to be pathogenic (PMID: 11865300, 21398687). - |
Pathogenic, criteria provided, single submitter | clinical testing | GeneDx | Jun 14, 2019 | Canonical splice site variant predicted to result in an in-frame deletion of a critical region [Exon 5 with multiple PATH missense variants and the substrate binding region]; Not observed in large population cohorts (Lek et al., 2016) - |
Fumarase deficiency Pathogenic:1
Likely pathogenic, criteria provided, single submitter | clinical testing | Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Feb 27, 2018 | Variant summary: FH c.738+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Five predict the variant abolishes a 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 245936 control chromosomes. To our knowledge, no occurrence of c.738+2T>C in individuals affected with Hereditary Leiomyomatosis and Renal Cell Cancer and no experimental evidence demonstrating its impact on protein function have been reported. However, a different change at the same nucleotide (c.738+2T>A) has been reported in a patient affected with multiple cutaneous leiomyomas. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, and classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. - |
Hereditary cancer-predisposing syndrome Pathogenic:1
Pathogenic, criteria provided, single submitter | clinical testing | Ambry Genetics | Sep 25, 2023 | The c.738+2T>C intronic pathogenic mutation results from a T to C substitution two nucleotides after coding exon 5 in the FH gene. This nucleotide position is highly conserved in available vertebrate species. This alteration has been observed in at least one individual with a personal and/or family history that is consistent with FH-related disease (Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In silico splice site analysis predicts that this alteration will weaken the native splice donor site and may result in the creation or strengthening of a novel splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. - |
Computational scores
Source:
Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
D
BayesDel_noAF
Pathogenic
CADD
Pathogenic
DANN
Uncertain
Eigen
Pathogenic
Eigen_PC
Pathogenic
FATHMM_MKL
Pathogenic
D
MutationTaster
Benign
D
GERP RS
Splicing
Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
dbscSNV1_RF
Benign
SpliceAI score (max)
Details are displayed if max score is > 0.2
DS_DG_spliceai
Position offset: 43
DS_DL_spliceai
Position offset: 2
Find out detailed SpliceAI scores and Pangolin per-transcript scores at