1-1232291-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_080605.4(B3GALT6):c.13C>T(p.Arg5Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000191 in 835,632 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000019 (0 hom.)
• Consequence: B3GALT6 NM_080605.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.97

Genes affected

B3GALT6 (HGNC:17978): (beta-1,3-galactosyltransferase 6) The enzyme encoded by this intronless gene is a beta-1,3-galactosyltransferase found in the medial Golgi apparatus, where it catalyzes the transfer of galactose from UDP-galactose to substrates containing a terminal beta-linked galactose moiety. The encoded enzyme has a particular affinity for galactose-beta-1,4-xylose found in the linker region of glycosamines. This enzyme is required for glycosaminoglycan synthesis. [provided by RefSeq, Jun 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
B3GALT6	NM_080605.4	c.13C>T	p.Arg5Trp	missense_variant	1/1	ENST00000379198.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
B3GALT6	ENST00000379198.5	c.13C>T	p.Arg5Trp	missense_variant	1/1		NM_080605.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.0000191 AC: 16 AN: 835632 Hom.: 0 Cov.: 29 AF XY: 0.0000155 AC XY: 6 AN XY: 386110

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: 0.0000210

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spondyloepimetaphyseal dysplasia with joint laxity;C3809210:Ehlers-Danlos syndrome, spondylodysplastic type, 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 23, 2021

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: "Not Available"; 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. This variant has not been reported in the literature in individuals with B3GALT6-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This sequence change replaces arginine with tryptophan at codon 5 of the B3GALT6 protein (p.Arg5Trp). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and tryptophan. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Benign	-0.032	T
BayesDel_noAF	Benign	-0.28
Cadd	Uncertain	23
Dann	Uncertain	0.99
DEOGEN2	Benign	0.074	T;T
Eigen	Benign	-0.026
Eigen_PC	Benign	-0.11
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.88	D
MetaRNN	Uncertain	0.56	D;D
MetaSVM	Benign	-0.90	T
MutationAssessor	Benign	1.8	L;L
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.93	D
Polyphen		1.0	D;D
Vest4		0.41
MutPred		0.52		Loss of disorder (P = 0.0036);Loss of disorder (P = 0.0036);
MVP		0.85
MPC		0.96
ClinPred		0.98	D
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.6
Varity_R		0.47
gMVP		0.66

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: rs1638529780; hg19: chr1-1167671;