9-128947108-G-A

Variant names:

• chr9-128947108-G-A
• rs876657785
• NM_014908.4:c.196C>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Strong

The NM_014908.4(DOLK):​c.196C>T​(p.Gln66*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,726 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 (★★). Synonymous variant affecting the same amino acid position (i.e. Q66Q) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: DOLK NM_014908.4 stop_gained
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.98
• Publications: 1 publications found

Genes affected

DOLK (HGNC:23406): (dolichol kinase) The protein encoded by this gene catalyzes the CTP-mediated phosphorylation of dolichol, and is involved in the synthesis of Dol-P-Man, which is an essential glycosyl carrier lipid for C- and O-mannosylation, N- and O-linked glycosylation of proteins, and for the biosynthesis of glycosyl phosphatidylinositol anchors in endoplasmic reticulum. Mutations in this gene are associated with dolichol kinase deficiency.[provided by RefSeq, Apr 2010]

DOLK Gene-Disease associations (from GenCC):

• DK1-congenital disorder of glycosylation

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, G2P
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000251184 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 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. There are 15 pathogenic variants in the truncated region.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DOLK	NM_014908.4	c.196C>T	p.Gln66*	stop_gained	Exon 1 of 1	ENST00000372586.4	NP_055723.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DOLK	ENST00000372586.4	c.196C>T	p.Gln66*	stop_gained	Exon 1 of 1	6	NM_014908.4	ENSP00000361667.3
ENSG00000251184	ENST00000482796.1	c.39-2081G>A		intron_variant	Intron 1 of 4	2		ENSP00000417556.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461726 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727182

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53258

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1112008

Other (OTH) AF: 0.0000331 AC: 2 AN: 60396

GnomAD4 genome Cov.: 31

Alfa AF: 0.000122 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Sep 10, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The p.Gln66X va riant in DOLK has not been previously reported in individuals with cardiomyopath y and was absent from large population studies. This nonsense variant leads to a premature termination codon at position 66. Because this gene contains only a s ingle exon, this alteration is more likely to escape nonsense mediated decay (NM D) and result in a truncated protein. It is unclear how this alteration will imp act the protein's function. Studies on previously reported DOLK variants suggest that reduced protein function is disease-causing. However, there is limited inf ormation on the variant spectrum of this gene and the significance of truncating variants or complete loss of protein function remain unclear. In summary, while there is some suspicion for a pathogenic role, the clinical significance of the p.Gln66X variant is uncertain. -

DK1-congenital disorder of glycosylation Uncertain:1

Nov 22, 2022

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.Gln66*) in the DOLK gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 473 amino acid(s) of the DOLK protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DOLK-related conditions. ClinVar contains an entry for this variant (Variation ID: 228618). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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	0.63	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	38
DANN	Uncertain	1.0
Eigen	Pathogenic	0.78
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Benign	0.35	N
PhyloP100		2.0
Vest4		0.73
GERP RS		3.6
PromoterAI		0.0063	Neutral
Mutation Taster		=26/174	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

Other links and lift over

dbSNP: rs876657785; hg19: chr9-131709387;