rs369083786

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_ModeratePM2PP3_StrongPP5_Very_Strong

The NM_024854.5(PYROXD1):c.285+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000194 in 1,581,730 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/2 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00020 ( 0 hom. )

Consequence

PYROXD1
NM_024854.5 splice_donor

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 8.45

Variant links:

Genes affected

PYROXD1 (HGNC:26162): (pyridine nucleotide-disulphide oxidoreductase domain 1) This gene encodes a nuclear-cytoplasmic pyridine nucleotide-disulphide reductase (PNDR). PNDRs are flavoproteins that catalyze the pyridine nucleotide-dependent reduction of thiol residues in other proteins. The encoded protein belongs to the class I pyridine nucleotide-disulphide oxidoreductase family but lacks the C-terminal dimerization domain found in other family members and instead has a C-terminal nitrile reductase domain. It localizes to the nucleus and to striated sarcomeric compartments. Naturally occurring mutations in this gene cause early-onset myopathy with internalized nuclei and myofibrillar disorganization. A pseudogene of this gene has been defined on chromosome 11. [provided by RefSeq, Apr 2017]

PYROXD1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PVS1

Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.07917498 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, dbscSNV1_RF. No scorers claiming Uncertain. No scorers claiming Benign.

PP5

Variant 12-21445467-G-A is Pathogenic according to our data. Variant chr12-21445467-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 372278.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr12-21445467-G-A is described in Lovd as [Pathogenic]. Variant chr12-21445467-G-A is described in Lovd as [Likely_pathogenic]. Variant chr12-21445467-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PYROXD1	NM_024854.5 linkuse as main transcript	c.285+1G>A		splice_donor_variant		ENST00000240651.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PYROXD1	ENST00000240651.14 linkuse as main transcript	c.285+1G>A		splice_donor_variant		1	NM_024854.5	P1	Q8WU10-1

Frequencies

GnomAD3 genomes

AF:

0.0000986

AC:

AN:

152152

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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:

0.000162

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000864

AC:

AN:

219878

Hom.:

AF XY:

0.0000837

AC XY:

AN XY:

119432

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000162

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000143

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000204

AC:

292

AN:

1429578

Hom.:

Cov.:

AF XY:

0.000193

AC XY:

137

AN XY:

710694

show subpopulations

Gnomad4 AFR exome

AF:

0.0000634

Gnomad4 AMR exome

AF:

0.000145

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000251

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000250

Gnomad4 OTH exome

AF:

0.000119

GnomAD4 genome

AF:

0.0000986

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000162

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000165

Hom.:

Bravo

AF:

0.000110

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000494

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Myofibrillar myopathy 8

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jan 23, 2019	This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 19, 2016	- -
Likely pathogenic, criteria provided, single submitter	curation	Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard	May 02, 2023	The heterozygous c.285+1G>A variant in PYROXD1 was identified by our study, in the compound heterozygous state with a variant of uncertain significance (NC_000012.12:g.21461062T>G), in one individual with limb girdle myopathy. Trio exome analysis revealed that this variant was in trans with a variant of uncertain significance (NC_000012.12:g.21461062T>G). The c.285+1G>A variant in PYROXD1 has been reported in six individuals with myofibrillar myopathy 8 (PMID: 27745833, PMID: 33333461, PMID: 32528171), but has been identified in 0.02% (4/25598) of Latino/Admixed American chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs369083786). Although this variant has been seen in the general population in a heterozygous state, its frequency is not high enough to rule out a pathogenic role. This variant has also been reported in ClinVar (Variation ID: 372278) and has been interpreted as pathogenic by Invitae, Baylor Genetics, and OMIM, and as likely pathogenic by GeneDx. Of these six previously reported individuals, four were homozygotes (PMID: 32528171) and 1 was a compound heterozygote who carried a variant of uncertain significance in trans (PMID: 27745833, ClinVar ID: 372279), and, in addition, the patient identified by our study was a compound heterozygote who carried a variant of uncertain significance (NC_000012.12:g.21461062T>G) in trans, which increases the likelihood that the c.285+1G>A variant is pathogenic. RT-PCR analysis performed on affected muscle tissue showed evidence of exon skipping of exon 3 (PMID: 27745833). Exon 3 (NM_024854.5) is in-frame with 120 nucleotides (40 codons). This variant is located in the 5' splice region. Computational tools predict a splicing impact, though this information is not predictive enough to determine pathogenicity. Loss of function of the PYROXD1 gene is an established disease mechanism in autosomal recessive myofibrillar myopathy 8. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal recessive myofibrillar myopathy 8. ACMG/AMP Criteria applied: PVS1_Moderate, PM3_Strong, PS3_Moderate (Richards 2015). -

not provided

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 01, 2024	This sequence change affects a donor splice site in intron 3 of the PYROXD1 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely results in a shortened protein product. This variant is present in population databases (rs369083786, gnomAD 0.02%). Disruption of this splice site has been observed in individual(s) with early-onset myopathy (PMID: 27745833, 31455395). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 372278). Studies have shown that disruption of this splice site results in skipping of exon 3, but is expected to preserve the integrity of the reading-frame (PMID: 27745833). For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	GeneDx	May 06, 2023	Canonical splice site variant predicted to result in an in-frame loss of the adjacent exon in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 27745833, 31455395, 32528171, 34694888, 33333461) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.38

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.98

FATHMM_MKL

Pathogenic

1.0

MutationTaster

Benign

1.0

D;D;D;D

GERP RS

5.3

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.94

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.99

Position offset: -1

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over