1-20652412-G-T

Position:

• chr1-20652412-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_005216.5(DDOST):​c.1287C>A​(p.Phe429Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: DDOST NM_005216.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.23

Genes affected

DDOST (HGNC:2728): (dolichyl-diphosphooligosaccharide--protein glycosyltransferase non-catalytic subunit) This gene encodes a component of the oligosaccharyltransferase complex which catalyzes the transfer of high-mannose oligosaccharides to asparagine residues on nascent polypeptides in the lumen of the rough endoplasmic reticulum. The protein complex co-purifies with ribosomes. The product of this gene is also implicated in the processing of advanced glycation endproducts (AGEs), which form from non-enzymatic reactions between sugars and proteins or lipids and are associated with aging and hyperglycemia. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.914

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DDOST	NM_005216.5	c.1287C>A	p.Phe429Leu	missense_variant	11/11	ENST00000602624.7	NP_005207.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DDOST	ENST00000602624.7	c.1287C>A	p.Phe429Leu	missense_variant	11/11	1	NM_005216.5	ENSP00000473655	P1
DDOST	ENST00000415136.6	c.1338C>A	p.Phe446Leu	missense_variant	11/11	1		ENSP00000399457

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250558 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135496

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital disorder of glycosylation type Ir Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 05, 2023

This sequence change replaces phenylalanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 446 of the DDOST protein (p.Phe446Leu). This variant is present in population databases (rs760390881, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with DDOST-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.29
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.71	D;T;D
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.94	D;D;.
M_CAP	Benign	0.075	D
MetaRNN	Pathogenic	0.91	D;D;D
MetaSVM	Uncertain	0.17	D
MutationAssessor	Uncertain	2.6	M;.;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-5.2	.;.;D
REVEL	Pathogenic	0.77
Sift	Uncertain	0.026	.;.;D
Sift4G	Uncertain	0.020	D;D;D
Polyphen		0.22	B;.;B
Vest4		0.92
MutPred		0.80		Gain of catalytic residue at F446 (P = 0.0661);.;Gain of catalytic residue at F446 (P = 0.0661);
MVP		0.87
MPC		0.49
ClinPred		0.89	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.80
gMVP		0.59

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: rs760390881; hg19: chr1-20978905;