rs1556788657

Positions:

• chrX-47202496-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_003334.4(UBA1):​c.1048C>T​(p.Arg350Cys) 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 benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R350H) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 9.2e-7 (0 hom. 1 hem.)
  • Failed GnomAD Quality Control
• Consequence: UBA1 NM_003334.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.59

Genes affected

UBA1 (HGNC:12469): (ubiquitin like modifier activating enzyme 1) The protein encoded by this gene catalyzes the first step in ubiquitin conjugation to mark cellular proteins for degradation. This gene complements an X-linked mouse temperature-sensitive defect in DNA synthesis, and thus may function in DNA repair. It is part of a gene cluster on chromosome Xp11.23. Alternatively spliced transcript variants that encode the same protein have been described. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), UBA1. . Gene score misZ 3.4752 (greater than the threshold 3.09). GenCC has associacion of gene with infantile-onset X-linked spinal muscular atrophy, inflammatory disease.
• BP4: Computational evidence support a benign effect (MetaRNN=0.23121536).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
UBA1	NM_003334.4	c.1048C>T	p.Arg350Cys	missense_variant	10/26	ENST00000335972.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
UBA1	ENST00000335972.11	c.1048C>T	p.Arg350Cys	missense_variant	10/26	1	NM_003334.4	P1
UBA1	ENST00000377351.8	c.1048C>T	p.Arg350Cys	missense_variant	10/26	1		P1

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 9.20e-7 AC: 1 AN: 1087260 Hom.: 0 Cov.: 33 AF XY: 0.00000282 AC XY: 1 AN XY: 355206

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: 0.00000120

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 24

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Infantile-onset X-linked spinal muscular atrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 02, 2017

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with UBA1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with cysteine at codon 350 of the UBA1 protein (p.Arg350Cys). The arginine residue is moderately conserved and there is a large physicochemical difference between arginine and cysteine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.094
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.58
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.30	T;T
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.99	D;.
M_CAP	Benign	0.033	D
MetaRNN	Benign	0.23	T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.8	L;L
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.34	T
PROVEAN	Uncertain	-3.9	D;D
REVEL	Benign	0.068
Sift	Benign	0.18	T;T
Sift4G	Benign	0.18	T;T
Polyphen		0.97	D;D
Vest4		0.32
MutPred		0.33		Gain of catalytic residue at P349 (P = 0.0104);Gain of catalytic residue at P349 (P = 0.0104);
MVP		0.20
MPC		0.92
ClinPred		0.93	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2
Varity_R		0.45
gMVP		0.62

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: rs1556788657; hg19: chrX-47061895; COSMIC: COSV60114264; COSMIC: COSV60114264;