chr17-49142144-C-T

Variant names:

• chr17-49142144-C-T
• rs749775812
• NM_001159387.2:c.325C>T

Variant summary

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

The NM_001159387.2(B4GALNT2):​c.325C>T​(p.Gln109*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000123 in 1,461,842 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: B4GALNT2 NM_001159387.2 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.739

Genes affected

B4GALNT2 (HGNC:24136): (beta-1,4-N-acetyl-galactosaminyltransferase 2 (SID blood group)) B4GALNT2 catalyzes the last step in the biosynthesis of the human Sd(a) antigen through the addition of an N-acetylgalactosamine residue via a beta-1,4 linkage to a subterminal galactose residue substituted with an alpha-2,3-linked sialic acid. B4GALNT2 also catalyzes the last step in the biosynthesis of the Cad antigen (Montiel et al., 2003 [PubMed 12678917]).[supplied by OMIM, Mar 2008]

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 rank	MANE	Protein	UniProt
B4GALNT2	NM_001159387.2	c.325C>T	p.Gln109*	stop_gained	Exon 3 of 11	ENST00000393354.7	NP_001152859.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
B4GALNT2	ENST00000393354.7	c.325C>T	p.Gln109*	stop_gained	Exon 3 of 11	1	NM_001159387.2	ENSP00000377022.3
B4GALNT2	ENST00000300404.2	c.505C>T	p.Gln169*	stop_gained	Exon 3 of 11	1		ENSP00000300404.2
B4GALNT2	ENST00000504681.5	c.247C>T	p.Gln83*	stop_gained	Exon 3 of 11	2		ENSP00000425510.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251448 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135900

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000123 AC: 18 AN: 1461842 Hom.: 0 Cov.: 30 AF XY: 0.0000110 AC XY: 8 AN XY: 727230

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: 0.0000162

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Pathogenic	0.76
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Benign	0.67	D
Vest4		0.28
GERP RS		3.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.25		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.25		Position offset: 28

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs749775812; hg19: chr17-47219506;