rs137853090

chr2-165761928-G-Achr2-165761928-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM2 PM5 BP4

The NM_004482.4(GALNT3):c.815C>T(p.Thr272Met) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,614,030 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T272K) has been classified as Pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: GALNT3 NM_004482.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.05

Genes affected

GALNT3 (HGNC:4125): (polypeptide N-acetylgalactosaminyltransferase 3) This gene encodes UDP-GalNAc transferase 3, a member of the GalNAc-transferases family. This family transfers an N-acetyl galactosamine to the hydroxyl group of a serine or threonine residue in the first step of O-linked oligosaccharide biosynthesis. Individual GalNAc-transferases have distinct activities and initiation of O-glycosylation is regulated by a repertoire of GalNAc-transferases. The protein encoded by this gene is highly homologous to other family members, however the enzymes have different substrate specificities. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-165761928-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 7799.Status of the report is no_assertion_criteria_provided, 0 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.28027648).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GALNT3	NM_004482.4	c.815C>T	p.Thr272Met	missense_variant	4/11	ENST00000392701.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GALNT3	ENST00000392701.8	c.815C>T	p.Thr272Met	missense_variant	4/11	1	NM_004482.4	P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152068 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: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 251344 Hom.: 0 AF XY: 0.0000221 AC XY: 3 AN XY: 135840

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000272

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461844 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727228

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000101

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74406

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.0000247 AC: 3

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

Invitae

Jul 27, 2022

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 272 of the GALNT3 protein (p.Thr272Met). This variant is present in population databases (rs137853090, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with GALNT3-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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	Benign	0.19
BayesDel_addAF	Benign	-0.012	T
BayesDel_noAF	Uncertain	0.050
Cadd	Pathogenic	30
Dann	Uncertain	1.0
DEOGEN2	Benign	0.11	T;T
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Pathogenic	0.97	D;D
M_CAP	Benign	0.038	D
MetaRNN	Benign	0.28	T;T
MetaSVM	Benign	-0.52	T
MutationAssessor	Benign	1.4	L;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.76	T
PROVEAN	Benign	-0.18	N;N
REVEL	Benign	0.27
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0030	D;D
Polyphen		0.99	D;.
Vest4		0.83
MutPred		0.55		Gain of sheet (P = 0.1539);Gain of sheet (P = 0.1539);
MVP		0.82
MPC		0.48
ClinPred		0.43	T
GERP RS		5.1
Varity_R		0.48
gMVP		0.79

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs137853090; hg19: chr2-166618438;