chr9-33112748-T-TA

Variant names:

• chr9-33112748-T-TA
• rs779761525
• NM_001497.4:c.*705dupT

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_001497.4(B4GALT1):​c.*705dupT variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000086 in 151,218 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000086 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: B4GALT1 NM_001497.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.245
• Publications: 0 publications found

Genes affected

B4GALT1 (HGNC:924): (beta-1,4-galactosyltransferase 1) This gene is one of seven beta-1,4-galactosyltransferase (beta4GalT) genes. They encode type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose; all transfer galactose in a beta1,4 linkage to similar acceptor sugars: GlcNAc, Glc, and Xyl. Each beta4GalT has a distinct function in the biosynthesis of different glycoconjugates and saccharide structures. As type II membrane proteins, they have an N-terminal hydrophobic signal sequence that directs the protein to the Golgi apparatus and which then remains uncleaved to function as a transmembrane anchor. By sequence similarity, the beta4GalTs form four groups: beta4GalT1 and beta4GalT2, beta4GalT3 and beta4GalT4, beta4GalT5 and beta4GalT6, and beta4GalT7. This gene is unique among the beta4GalT genes because it encodes an enzyme that participates both in glycoconjugate and lactose biosynthesis. For the first activity, the enzyme adds galactose to N-acetylglucosamine residues that are either monosaccharides or the nonreducing ends of glycoprotein carbohydrate chains. The second activity is restricted to lactating mammary tissues where the enzyme forms a heterodimer with alpha-lactalbumin to catalyze UDP-galactose + D-glucose <=> UDP + lactose. The two enzymatic forms result from alternate transcription initiation sites and post-translational processing. Two transcripts, which differ only at the 5' end, with approximate lengths of 4.1 kb and 3.9 kb encode the same protein. The longer transcript encodes the type II membrane-bound, trans-Golgi resident protein involved in glycoconjugate biosynthesis. The shorter transcript encodes a protein which is cleaved to form the soluble lactose synthase. [provided by RefSeq, Jul 2008]

B4GALT1 Gene-Disease associations (from GenCC):

• B4GALT1-congenital disorder of glycosylation

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P, Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001497.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B4GALT1	NM_001497.4	MANE Select	c.*705dupT		3_prime_UTR	Exon 6 of 6	NP_001488.2
	B4GALT1	NM_001378495.1		c.*705dupT		3_prime_UTR	Exon 6 of 6	NP_001365424.1	P15291-2
	B4GALT1	NM_001378496.1		c.*705dupT		3_prime_UTR	Exon 5 of 5	NP_001365425.1	W6MEN3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B4GALT1	ENST00000379731.5	TSL:1 MANE Select	c.*705dupT		3_prime_UTR	Exon 6 of 6	ENSP00000369055.4	P15291-1
	B4GALT1	ENST00000535206.6	TSL:1	c.649-7968dupT		intron	N/A	ENSP00000440341.1	Q86XA6
	B4GALT1	ENST00000860372.1		c.*705dupT		3_prime_UTR	Exon 7 of 7	ENSP00000530431.1

Frequencies

GnomAD3 genomes AF: 0.0000860 AC: 13 AN: 151104 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000243

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000661

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00155

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.0000295

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 820 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 444

African (AFR) AC: 0 AN: 0

American (AMR) AF: 0.00 AC: 0 AN: 40

Ashkenazi Jewish (ASJ) AC: 0 AN: 0

East Asian (EAS) AF: 0.00 AC: 0 AN: 4

South Asian (SAS) AF: 0.00 AC: 0 AN: 18

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 422

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 328

Other (OTH) AF: 0.00 AC: 0 AN: 8

GnomAD4 genome AF: 0.0000860 AC: 13 AN: 151218 Hom.: 0 Cov.: 32 AF XY: 0.0000677 AC XY: 5 AN XY: 73874

African (AFR) AF: 0.0000243 AC: 1 AN: 41200

American (AMR) AF: 0.0000661 AC: 1 AN: 15140

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3458

East Asian (EAS) AF: 0.00155 AC: 8 AN: 5160

South Asian (SAS) AF: 0.00 AC: 0 AN: 4770

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10410

Middle Eastern (MID) AF: 0.00342 AC: 1 AN: 292

European-Non Finnish (NFE) AF: 0.0000295 AC: 2 AN: 67780

Other (OTH) AF: 0.00 AC: 0 AN: 2096

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.000102

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital disorder of glycosylation (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.24
Mutation Taster		=100/0	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: rs779761525; hg19: chr9-33112746;