chr1-146019672-T-A

Position:

• chr1-146019672-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM2 PP5_Moderate BP4

The NM_145277.5(HJV):​c.-180A>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,454 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HJV NM_145277.5 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: -0.0690

Genes affected

HJV (HGNC:4887): (hemojuvelin BMP co-receptor) The product of this gene is involved in iron metabolism. It may be a component of the signaling pathway which activates hepcidin or it may act as a modulator of hepcidin expression. It could also represent the cellular receptor for hepcidin. Two uORFs in the 5' UTR negatively regulate the expression and activity of the encoded protein. Alternatively spliced transcript variants encoding different isoforms have been identified for this gene. Defects in this gene are the cause of hemochromatosis type 2A, also called juvenile hemochromatosis (JH). JH is an early-onset autosomal recessive disorder due to severe iron overload resulting in hypogonadotrophic hypogonadism, hepatic fibrosis or cirrhosis and cardiomyopathy, occurring typically before age of 30. [provided by RefSeq, Oct 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-146019672-T-A is Pathogenic according to our data. Variant chr1-146019672-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 2373.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HJV	NM_213653.4	c.160A>T	p.Arg54*	stop_gained	3/4	ENST00000336751.11	NP_998818.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HJV	ENST00000336751.11	c.160A>T	p.Arg54*	stop_gained	3/4	2	NM_213653.4	ENSP00000337014.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461454 Hom.: 0 Cov.: 37 AF XY: 0.00000138 AC XY: 1 AN XY: 727048

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Hemochromatosis type 2A Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jul 01, 2008

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 14, 2023

This sequence change creates a premature translational stop signal (p.Arg54*) in the HJV gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HJV are known to be pathogenic (PMID: 20301349, 22408404). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with hereditary hemochromatosis (PMID: 18492090). ClinVar contains an entry for this variant (Variation ID: 2373). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Pathogenic	32
DANN	Uncertain	0.99
Vest4		0.82

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: rs121434375; hg19: chr1-145415341;