rs202147607

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM2PP3PP5_Moderate

The NM_000140.5(FECH):​c.1137+3A>G variant causes a splice region, intron change. The variant allele was found at a frequency of 0.00000249 in 1,603,560 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

FECH
NM_000140.5 splice_region, intron

Scores

2
Splicing: ADA: 0.9996
2

Clinical Significance

Pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 4.16

Publications

3 publications found
Variant links:
Genes affected
FECH (HGNC:3647): (ferrochelatase) The protein encoded by this gene is localized to the mitochondrion, where it catalyzes the insertion of the ferrous form of iron into protoporphyrin IX in the heme synthesis pathway. Mutations in this gene are associated with erythropoietic protoporphyria. Two transcript variants encoding different isoforms have been found for this gene. A pseudogene of this gene is found on chromosome 3.[provided by RefSeq, May 2010]
FECH Gene-Disease associations (from GenCC):
  • protoporphyria, erythropoietic, 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Laboratory for Molecular Medicine, ClinGen, Labcorp Genetics (formerly Invitae)
  • autosomal erythropoietic protoporphyria
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 18-57551312-T-C is Pathogenic according to our data. Variant chr18-57551312-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 553.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FECHNM_000140.5 linkc.1137+3A>G splice_region_variant, intron_variant Intron 10 of 10 ENST00000262093.11 NP_000131.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FECHENST00000262093.11 linkc.1137+3A>G splice_region_variant, intron_variant Intron 10 of 10 1 NM_000140.5 ENSP00000262093.6

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152226
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
250950
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000207
AC:
3
AN:
1451216
Hom.:
0
Cov.:
29
AF XY:
0.00000138
AC XY:
1
AN XY:
722678
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33264
American (AMR)
AF:
0.00
AC:
0
AN:
44706
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26058
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39588
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86006
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53342
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5742
European-Non Finnish (NFE)
AF:
0.00000272
AC:
3
AN:
1102458
Other (OTH)
AF:
0.00
AC:
0
AN:
60052
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000656
AC:
1
AN:
152344
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74492
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41570
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.275
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Jul 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 10 of the FECH gene. It does not directly change the encoded amino acid sequence of the FECH protein. RNA analysis indicates that this variant induces altered splicing and likely results in a shortened protein product. This variant is present in population databases (rs202147607, gnomAD 0.0009%). This variant has been observed in individual(s) with clinical features of erythropoietic protoporphyria (PMID: 7910885; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 553). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant results in skipping of exon 10, but is expected to preserve the integrity of the reading-frame (PMID: 7910885). For these reasons, this variant has been classified as Pathogenic.

Protoporphyria, erythropoietic, 1 Pathogenic:1
Jun 04, 1994
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.27
CADD
Benign
17
DANN
Benign
0.97
PhyloP100
4.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.8
Mutation Taster
=4/96
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.99
SpliceAI score (max)
0.77
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.77
Position offset: 3

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

Publications

Other links and lift over

dbSNP: rs202147607; hg19: chr18-55218544; API