rs900948973

Positions:

• chr1-43736285-G-A
• chr1-43736285-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_006279.5(ST3GAL3):​c.23G>A​(p.Arg8His) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,868 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R8L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ST3GAL3 NM_006279.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.71

Genes affected

ST3GAL3 (HGNC:10866): (ST3 beta-galactoside alpha-2,3-sialyltransferase 3) The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. The encoded protein is normally found in the Golgi apparatus but can be proteolytically processed to a soluble form. This protein is a member of glycosyltransferase family 29. Mutations in this gene have been associated with a form of autosomal recessive nonsymdromic cognitive disability as well as infantile epileptic encephalopathy. Multiple transcript variants encoding several different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]

ENSG00000284989 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.794

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ST3GAL3	NM_006279.5	c.23G>A	p.Arg8His	missense_variant	2/12	ENST00000347631.8	NP_006270.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ST3GAL3	ENST00000347631.8	c.23G>A	p.Arg8His	missense_variant	2/12	5	NM_006279.5	ENSP00000317192.6
ENSG00000284989	ENST00000645057.1	n.*1345G>A		non_coding_transcript_exon_variant	16/26			ENSP00000494063.1
ENSG00000284989	ENST00000645057.1	n.*1345G>A		3_prime_UTR_variant	16/26			ENSP00000494063.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461868 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727232

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Sep 23, 2015

- -

Early infantile epileptic encephalopathy with suppression bursts Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 07, 2023

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 8 of the ST3GAL3 protein (p.Arg8His). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ST3GAL3-related conditions. ClinVar contains an entry for this variant (Variation ID: 436878). 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
AlphaMissense	Uncertain	0.51
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.13	T;.;.;.;.;.;.;.;.;.;.;.;.;.;.;T;.;.;.;.;.;T;.;.;.;.;.;.;.;.;.;.;.;.
Eigen	Uncertain	0.66
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.99	.;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.;D;.;.
M_CAP	Benign	0.025	D
MetaRNN	Pathogenic	0.79	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.030	D
MutationAssessor	Benign	0.97	L;L;L;L;L;L;L;.;.;.;L;.;L;L;L;L;.;L;.;.;.;L;.;.;L;L;L;L;L;L;L;L;L;L
PrimateAI	Pathogenic	0.90	D
PROVEAN	Benign	-1.5	N;N;N;N;N;N;N;.;.;.;N;.;N;.;N;.;.;N;.;N;.;.;N;.;N;D;N;N;N;N;D;N;N;N
REVEL	Uncertain	0.41
Sift	Benign	0.17	T;T;T;T;T;T;T;.;.;.;T;.;T;.;T;.;.;T;.;T;.;.;T;.;T;T;T;T;T;T;T;T;T;T
Sift4G	Benign	0.36	T;T;T;T;T;T;T;.;.;.;T;.;T;.;T;.;.;T;.;T;.;.;T;.;T;T;T;T;T;T;T;T;T;T
Polyphen		1.0	D;D;D;.;D;D;D;.;.;.;.;.;D;D;D;D;.;D;.;.;.;D;.;.;D;D;D;D;.;D;D;D;.;D
Vest4		0.67
MutPred		0.74		Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);
MVP		0.92
MPC		0.71
ClinPred		0.84	D
GERP RS		5.9
Varity_R		0.10
gMVP		0.57

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: rs900948973; hg19: chr1-44201956; COSMIC: COSV99496061; COSMIC: COSV99496061;