chr11-66346566-G-T

Position:

• chr11-66346566-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_006876.3(B4GAT1):​c.980C>A​(p.Pro327Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: B4GAT1 NM_006876.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.36

Genes affected

B4GAT1 (HGNC:15685): (beta-1,4-glucuronyltransferase 1) This gene encodes a member of the beta-1,3-N-acetylglucosaminyltransferase family. This enzyme is a type II transmembrane protein. It is essential for the synthesis of poly-N-acetyllactosamine, a determinant for the blood group i antigen. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.951

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
B4GAT1	NM_006876.3	c.980C>A	p.Pro327Gln	missense_variant	1/2	ENST00000311181.5	NP_006867.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
B4GAT1	ENST00000311181.5	c.980C>A	p.Pro327Gln	missense_variant	1/2	1	NM_006876.3	ENSP00000309096	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A13 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 08, 2022

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt B4GAT1 protein function. ClinVar contains an entry for this variant (Variation ID: 474252). This variant has not been reported in the literature in individuals affected with B4GAT1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with glutamine, which is neutral and polar, at codon 327 of the B4GAT1 protein (p.Pro327Gln). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.90	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Benign	0.062	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Uncertain	-0.21	T
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-8.0	D
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.81
MutPred		0.84		Gain of sheet (P = 0.0827);
MVP		0.24
MPC		1.9
ClinPred		1.0	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.80
gMVP		0.99

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: rs1555016420; hg19: chr11-66114037;