19-36055044-G-GT

Variant names:

• chr19-36055044-G-GT
• rs1568560516
• NM_001083961.2:c.75dupT

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001083961.2(WDR62):​c.75dupT​(p.Pro26SerfsTer54) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 33)
• Consequence: WDR62 NM_001083961.2 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.31
• Publications: 0 publications found

Genes affected

WDR62 (HGNC:24502): (WD repeat domain 62) This gene is proposed to play a role in cerebral cortical development. Mutations in this gene have been associated with microencephaly, cortical malformations, and cognitive disability. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2011]

WDR62 Gene-Disease associations (from GenCC):

• microcephaly 2, primary, autosomal recessive, with or without cortical malformations

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Ambry Genetics, Illumina, G2P, ClinGen
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 98 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
WDR62	NM_001083961.2	c.75dupT	p.Pro26SerfsTer54	frameshift_variant	Exon 1 of 32	ENST00000401500.7	NP_001077430.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
WDR62	ENST00000401500.7	c.75dupT	p.Pro26SerfsTer54	frameshift_variant	Exon 1 of 32	1	NM_001083961.2	ENSP00000384792.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Microcephaly 2, primary, autosomal recessive, with or without cortical malformations Uncertain:1

Oct 26, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The WDR62 c.73_74insT (p.Pro26SerfsTer54) variant results in a frameshift, and is predicted to result in premature termination of the protein. A literature search was performed for the gene, cDNA change, and amino acid change. No publications were found based on this search. This variant is not found in the 1000 Genomes Project, the Exome Sequencing Project, the Exome Aggregation Consortium or the Genome Aggregation Database. Based on the variant frequency, disease prevalence, disease penetrance, and inheritance mode, this variant could not be ruled out of causing disease. Due to the potential impact of frameshift variants and the lack of clarifying evidence, this variant is classified as a variant of unknown significance but suspicious for pathogenicity for primary microcephaly 2 with or without cortical malformations. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		1.3

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

Other links and lift over

dbSNP: rs1568560516; hg19: chr19-36545946;