rs752116461

Variant names:

• chr1-43920499-C-T
• rs752116461
• NM_006279.5:c.840C>T

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_Moderate BP6 BP7 BS1

The NM_006279.5(ST3GAL3):​c.840C>T​(p.Ala280Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000743 in 1,614,044 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000081 (0 hom.)
• Consequence: ST3GAL3 NM_006279.5 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: -3.16
• Publications: 0 publications found

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]

ST3GAL3 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 15

  Inheritance: AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• intellectual disability, autosomal recessive 12

  Inheritance: AR Classification: STRONG Submitted by: G2P
• complex neurodevelopmental disorder

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive non-syndromic intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000284989 (HGNC:):

ACMG classification

Our verdict: Benign. The variant received -8 ACMG points.

• BP4: Computational evidence support a benign effect (REVEL=0.125).
• BP6: Variant 1-43920499-C-T is Benign according to our data. Variant chr1-43920499-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 212311.
• BP7: Synonymous conserved (PhyloP=-3.16 with no splicing effect.
• BS1: Variant frequency is greater than expected in population sas. GnomAdExome4 allele frequency = 0.0000807 (118/1461892) while in subpopulation SAS AF = 0.000754 (65/86258). AF 95% confidence interval is 0.000606. There are 0 homozygotes in GnomAdExome4. There are 81 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006279.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ST3GAL3	NM_006279.5	MANE Select	c.840C>T	p.Ala280Ala	synonymous	Exon 10 of 12	NP_006270.1
	ST3GAL3	NM_001350619.2		c.885C>T	p.Ala295Ala	synonymous	Exon 10 of 13	NP_001337548.1
	ST3GAL3	NM_174963.5		c.1047C>T	p.Ala349Ala	synonymous	Exon 11 of 13	NP_777623.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ST3GAL3	ENST00000347631.8	TSL:5 MANE Select	c.840C>T	p.Ala280Ala	synonymous	Exon 10 of 12	ENSP00000317192.6
	ST3GAL3	ENST00000372372.7	TSL:1	c.954C>T	p.Ala318Ala	synonymous	Exon 10 of 12	ENSP00000361447.2
	ST3GAL3	ENST00000361746.9	TSL:1	c.933C>T	p.Ala311Ala	synonymous	Exon 11 of 13	ENSP00000354657.5

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152152 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000111 AC: 28 AN: 251422 AF XY: 0.000162

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000145

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000807 AC: 118 AN: 1461892 Hom.: 0 Cov.: 32 AF XY: 0.000111 AC XY: 81 AN XY: 727246

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000894 AC: 4 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.000754 AC: 65 AN: 86258

European-Finnish (FIN) AF: 0.0000562 AC: 3 AN: 53418

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.0000360 AC: 40 AN: 1112012

Other (OTH) AF: 0.0000828 AC: 5 AN: 60396

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152152 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74318

African (AFR) AF: 0.00 AC: 0 AN: 41432

American (AMR) AF: 0.00 AC: 0 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.000414 AC: 2 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68020

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.0000564 Hom.: 0

Bravo AF: 0.0000264

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	Developmental and epileptic encephalopathy (1)
-	-	1	Inborn genetic diseases (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.098
BayesDel_noAF	Benign	-0.54
CADD	Benign	2.4
DANN	Benign	0.64
PhyloP100		-3.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=88/12	polymorphism

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: rs752116461; hg19: chr1-44386171; COSMIC: COSV53522189; COSMIC: COSV53522189;