20-50958844-T-C

Position:

• chr20-50958844-T-C

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_014484.5(MOCS3):​c.2T>C​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000698 in 1,433,308 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: 33)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: MOCS3 NM_014484.5 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.80

Genes affected

MOCS3 (HGNC:15765): (molybdenum cofactor synthesis 3) Molybdenum cofactor (MoCo) is necessary for the function of all molybdoenzymes. The protein encoded by this gene adenylates and activates molybdopterin synthase, an enzyme required for biosynthesis of MoCo. This gene contains no introns. A pseudogene of this gene is present on chromosome 14. [provided by RefSeq, Nov 2012]

DPM1 (HGNC:3005): (dolichyl-phosphate mannosyltransferase subunit 1, catalytic) Dolichol-phosphate mannose (Dol-P-Man) serves as a donor of mannosyl residues on the lumenal side of the endoplasmic reticulum (ER). Lack of Dol-P-Man results in defective surface expression of GPI-anchored proteins. Dol-P-Man is synthesized from GDP-mannose and dolichol-phosphate on the cytosolic side of the ER by the enzyme dolichyl-phosphate mannosyltransferase. Human DPM1 lacks a carboxy-terminal transmembrane domain and signal sequence and is regulated by DPM2. Mutations in this gene are associated with congenital disorder of glycosylation type Ie. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2015]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MOCS3	NM_014484.5	c.2T>C	p.Met1?	start_lost	1/1	ENST00000244051.3	NP_055299.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MOCS3	ENST00000244051.3	c.2T>C	p.Met1?	start_lost	1/1	6	NM_014484.5	ENSP00000244051.1
DPM1	ENST00000683466.1	c.-258A>G		5_prime_UTR_variant	1/8			ENSP00000507404.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.98e-7 AC: 1 AN: 1433308 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 708342

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.15e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 16, 2022

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. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. ClinVar contains an entry for this variant (Variation ID: 1520498). This variant has not been reported in the literature in individuals affected with MOCS3-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects the initiator methionine of the MOCS3 mRNA. The next in-frame methionine is located at codon 119. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.11	T
Eigen	Benign	0.11
Eigen_PC	Benign	0.14
FATHMM_MKL	Benign	0.60	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.89	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Benign	-0.76	T
PROVEAN	Benign	-0.32	N
REVEL	Uncertain	0.33
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.81	P
Vest4		0.92
MutPred		0.98		Gain of phosphorylation at M1 (P = 0.0146);
MVP		0.91
ClinPred		1.0	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.94
gMVP		0.51

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr20-49575381;