19-35284962-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_StrongPM2

The NM_021175.4(HAMP):​c.175C>T​(p.Arg59*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,613,442 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 (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

HAMP
NM_021175.4 stop_gained

Scores

2
2
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.168

Publications

7 publications found
Variant links:
Genes affected
HAMP (HGNC:15598): (hepcidin antimicrobial peptide) The product encoded by this gene is involved in the maintenance of iron homeostasis, and it is necessary for the regulation of iron storage in macrophages, and for intestinal iron absorption. The preproprotein is post-translationally cleaved into mature peptides of 20, 22 and 25 amino acids, and these active peptides are rich in cysteines, which form intramolecular bonds that stabilize their beta-sheet structures. These peptides exhibit antimicrobial activity against bacteria and fungi. Mutations in this gene cause hemochromatosis type 2B, also known as juvenile hemochromatosis, a disease caused by severe iron overload that results in cardiomyopathy, cirrhosis, and endocrine failure. [provided by RefSeq, Oct 2014]
HAMP Gene-Disease associations (from GenCC):
  • hemochromatosis type 2B
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • hemochromatosis type 2
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.314 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HAMPNM_021175.4 linkc.175C>T p.Arg59* stop_gained Exon 3 of 3 ENST00000222304.5 NP_066998.1 P81172

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HAMPENST00000222304.5 linkc.175C>T p.Arg59* stop_gained Exon 3 of 3 1 NM_021175.4 ENSP00000222304.2 P81172
HAMPENST00000598398.5 linkc.175C>T p.Arg59* stop_gained Exon 4 of 4 2 ENSP00000471894.1 P81172
HAMPENST00000593580.1 linkn.2446C>T non_coding_transcript_exon_variant Exon 1 of 1 6
ENSG00000307628ENST00000827558.1 linkn.392-4089G>A intron_variant Intron 1 of 1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152094
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461348
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727022
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000990
AC:
11
AN:
1111510
Other (OTH)
AF:
0.00
AC:
0
AN:
60378
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000197
AC:
3
AN:
152094
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74298
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41374
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hereditary hemochromatosis Uncertain:1
Aug 12, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg59*) in the HAMP gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 26 amino acid(s) of the HAMP protein. This variant is not present in population databases (ExAC no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of hemochromatosis (PMID: 26310624, 26799139). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. This variant disrupts a region of the HAMP protein in which other variant(s) (p.Cys78Tyr) have been observed in individuals with HAMP-related conditions (PMID: 15099344). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. 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
BayesDel_addAF
Pathogenic
0.53
D
BayesDel_noAF
Pathogenic
0.33
CADD
Pathogenic
35
DANN
Uncertain
1.0
Eigen
Uncertain
0.29
Eigen_PC
Benign
0.038
FATHMM_MKL
Benign
0.12
N
PhyloP100
0.17
Vest4
0.88
GERP RS
2.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=15/185
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs779021719; hg19: chr19-35775865; COSMIC: COSV55885963; API