NM_025132.4:c.3484-2A>C

Variant names:

• chr4-39272978-A-C
• rs1553918403
• NM_025132.4:c.3484-2A>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_025132.4(WDR19):​c.3484-2A>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000139 in 1,440,036 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: WDR19 NM_025132.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:3
• Conservation: PhyloP100: 8.89
• Publications: 2 publications found

Genes affected

WDR19 (HGNC:18340): (WD repeat domain 19) The protein encoded by this gene is a member of the WD (tryptophan-aspartic acid) repeat family, which is a large family of structurally-related proteins known to participate in a wide range of cellular processes. Each WD repeat typically contains about 40 amino acids that are usually bracketed by glycine-histidine and tryptophan-aspartic acid (WD) dipeptides. This protein contains six WD repeats, three transmembrane domains, and a clathrin heavy-chain repeat. Mutations in this gene have been described in individuals with a wide range of disorders affecting function of the cilium. These disorders are known as ciliopathies, and include Jeune syndrome, Sensenbrenner syndromes, Senior-Loken syndrome, combined or isolated nephronophthisis (NPHP), and retinitis pigmentosa (RP). Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2015]

WDR19 Gene-Disease associations (from GenCC):

• asphyxiating thoracic dystrophy 5

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• cranioectodermal dysplasia 4

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• nephronophthisis 13

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• Senior-Loken syndrome 8

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• cranioectodermal dysplasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Jeune syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• nephronophthisis 1

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Senior-Loken syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-39272978-A-C is Pathogenic according to our data. Variant chr4-39272978-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 446636.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
WDR19	NM_025132.4	c.3484-2A>C		splice_acceptor_variant, intron_variant	Intron 31 of 36	ENST00000399820.8	NP_079408.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
WDR19	ENST00000399820.8	c.3484-2A>C		splice_acceptor_variant, intron_variant	Intron 31 of 36	1	NM_025132.4	ENSP00000382717.3
WDR19	ENST00000506869.5	n.*3065-2A>C		splice_acceptor_variant, intron_variant	Intron 30 of 35	2		ENSP00000424319.1
WDR19	ENST00000512095.5	n.2482-2A>C		splice_acceptor_variant, intron_variant	Intron 21 of 22	2
WDR19	ENST00000512534.5	n.49-2A>C		splice_acceptor_variant, intron_variant	Intron 1 of 5	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000139 AC: 2 AN: 1440036 Hom.: 0 Cov.: 30 AF XY: 0.00000140 AC XY: 1 AN XY: 714114

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33152

American (AMR) AF: 0.00 AC: 0 AN: 41274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25710

East Asian (EAS) AF: 0.00 AC: 0 AN: 39048

South Asian (SAS) AF: 0.00 AC: 0 AN: 81968

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52336

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5734

European-Non Finnish (NFE) AF: 0.00000182 AC: 2 AN: 1101140

Other (OTH) AF: 0.00 AC: 0 AN: 59674

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000037155), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, single submitter

Submissions by phenotype

Type IV short rib polydactyly syndrome Pathogenic:2

Jun 01, 2017

Dan Cohn Lab, University Of California Los Angeles

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

-

University of Washington Center for Mendelian Genomics, University of Washington

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Asphyxiating thoracic dystrophy 5;C4225376:Senior-Loken syndrome 8 Pathogenic:1

Nov 08, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects an acceptor splice site in intron 31 of the WDR19 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 WDR19 are known to be pathogenic (PMID: 22019273, 23559409, 23683095, 26275793, 27241786, 29068549). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with short-rib polydactyly syndrome (PMID: 29068549). ClinVar contains an entry for this variant (Variation ID: 446636). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.97
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		8.9
GERP RS		5.5
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AL_spliceai		1.0		Position offset: 2

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

Other links and lift over

dbSNP: rs1553918403; hg19: chr4-39274598;