3-161085942-CCC-GCG

Variant names:

• chr3-161085942-CCC-GCG
• NM_003781.4:c.811_813delGGGinsCGC
• B3GALNT1 p.Gly271Arg

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_003781.4(B3GALNT1):​c.811_813delGGGinsCGC​(p.Gly271Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: B3GALNT1 NM_003781.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.82
• Publications: 0 publications found

Genes affected

B3GALNT1 (HGNC:918): (beta-1,3-N-acetylgalactosaminyltransferase 1 (Globoside blood group)) This gene is a member of the beta-1,3-galactosyltransferase (beta3GalT) gene family. This family encodes type II membrane-bound glycoproteins with diverse enzymatic functions using different donor substrates (UDP-galactose and UDP-N-acetylglucosamine) and different acceptor sugars (N-acetylglucosamine, galactose, N-acetylgalactosamine). The beta3GalT genes are distantly related to the Drosophila Brainiac gene and have the protein coding sequence contained in a single exon. The beta3GalT proteins also contain conserved sequences not found in the beta4GalT or alpha3GalT proteins. The carbohydrate chains synthesized by these enzymes are designated as type 1, whereas beta4GalT enzymes synthesize type 2 carbohydrate chains. The ratio of type 1:type 2 chains changes during embryogenesis. By sequence similarity, the beta3GalT genes fall into at least two groups: beta3GalT4 and 4 other beta3GalT genes (beta3GalT1-3, beta3GalT5). The encoded protein of this gene does not use N-acetylglucosamine as an acceptor sugar at all. [provided by RefSeq, Mar 2017]

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003781.4. 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
	B3GALNT1	NM_003781.4	MANE Select	c.811_813delGGGinsCGC	p.Gly271Arg	missense	N/A	NP_003772.1	O75752
	B3GALNT1	NM_001349162.2		c.1171_1173delGGGinsCGC	p.Gly391Arg	missense	N/A	NP_001336091.1
	B3GALNT1	NM_001349163.2		c.1171_1173delGGGinsCGC	p.Gly391Arg	missense	N/A	NP_001336092.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B3GALNT1	ENST00000320474.10	TSL:1 MANE Select	c.811_813delGGGinsCGC	p.Gly271Arg	missense	N/A	ENSP00000323479.4	O75752
	B3GALNT1	ENST00000392781.7	TSL:1	c.811_813delGGGinsCGC	p.Gly271Arg	missense	N/A	ENSP00000376532.2	O75752
	B3GALNT1	ENST00000488170.5	TSL:1	c.811_813delGGGinsCGC	p.Gly271Arg	missense	N/A	ENSP00000420163.1	O75752

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.8

Splicing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr3-160803730;