NM_138459.5:c.803C>A

Variant names:

• chr6-117706936-C-A
• rs1554202852
• NM_138459.5:c.803C>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_138459.5(NUS1):​c.803C>A​(p.Ser268Tyr) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,460,276 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 (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: NUS1 NM_138459.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.88
• Publications: 0 publications found

Genes affected

NUS1 (HGNC:21042): (NUS1 dehydrodolichyl diphosphate synthase subunit) This gene encodes a type I single transmembrane domain receptor, which is a subunit of cis-prenyltransferase, and serves as a specific receptor for the neural and cardiovascular regulator Nogo-B. The encoded protein is essential for dolichol synthesis and protein glycosylation. This gene is highly expressed in non-small cell lung carcinomas as well as estrogen receptor-alpha positive breast cancer cells where it promotes epithelial mesenchymal transition. This gene is associated with the poor prognosis of human hepatocellular carcinoma patients. Naturally occurring mutations in this gene cause a congenital disorder of glycosylation and are associated with epilepsy. A knockout of the orthologous gene in mice causes embryonic lethality before day 6.5. Pseudogenes of this gene have been defined on chromosomes 13 and X. [provided by RefSeq, May 2017]

NUS1 Gene-Disease associations (from GenCC):

• intellectual disability, autosomal dominant 55, with seizures

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital disorder of glycosylation, type IAA

  Inheritance: AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.773

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_138459.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NUS1	NM_138459.5	MANE Select	c.803C>A	p.Ser268Tyr	missense	Exon 5 of 5	NP_612468.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NUS1	ENST00000368494.4	TSL:1 MANE Select	c.803C>A	p.Ser268Tyr	missense	Exon 5 of 5	ENSP00000357480.3
	NUS1	ENST00000885063.1		c.848C>A	p.Ser283Tyr	missense	Exon 6 of 6	ENSP00000555122.1
	NUS1	ENST00000923852.1		c.527C>A	p.Ser176Tyr	missense	Exon 3 of 3	ENSP00000593911.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460276 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726492

⚠️ 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: 33418

American (AMR) AF: 0.00 AC: 0 AN: 44698

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26064

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

South Asian (SAS) AF: 0.00 AC: 0 AN: 86202

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1110772

Other (OTH) AF: 0.00 AC: 0 AN: 60300

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital disorder of glycosylation, type IAA (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.60
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.17	T
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.92	D
M_CAP	Benign	0.039	D
MetaRNN	Pathogenic	0.77	D
MetaSVM	Benign	-1.0	T
MutationAssessor	Uncertain	2.2	M
PhyloP100		6.9
PrimateAI	Uncertain	0.69	T
PROVEAN	Uncertain	-4.2	D
REVEL	Uncertain	0.34
Sift	Uncertain	0.0030	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.67
MutPred		0.31		Gain of catalytic residue at S268 (P = 0.066)
MVP		0.38
MPC		1.6
ClinPred		0.99	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.87
gMVP		0.77
Mutation Taster		=36/64	disease causing

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: rs1554202852; hg19: chr6-118028099;