chr12-57626912-G-A

Variant names:

• chr12-57626912-G-A
• rs1060504132
• NM_001478.5:c.1434C>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_001478.5(B4GALNT1):​c.1434C>T​(p.Asp478Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: B4GALNT1 NM_001478.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.373
• Publications: 0 publications found

Genes affected

B4GALNT1 (HGNC:4117): (beta-1,4-N-acetyl-galactosaminyltransferase 1) GM2 and GD2 gangliosides are sialic acid-containing glycosphingolipids. GalNAc-T is the enzyme involved in the biosynthesis of G(M2) and G(D2) glycosphingolipids. GalNAc-T catalyzes the transfer of GalNAc into G(M3) and G(D3) by a beta-1,4 linkage, resulting in the synthesis of G(M2) and G(D2), respectively. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2013]

B4GALNT1 Gene-Disease associations (from GenCC):

• complex hereditary spastic paraplegia

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• hereditary spastic paraplegia 26

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

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.51).
• BP6: Variant 12-57626912-G-A is Benign according to our data. Variant chr12-57626912-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 413847.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-0.373 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001478.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B4GALNT1	NM_001478.5	MANE Select	c.1434C>T	p.Asp478Asp	synonymous	Exon 11 of 11	NP_001469.1
	B4GALNT1	NM_001413967.1		c.1602C>T	p.Asp534Asp	synonymous	Exon 11 of 11	NP_001400896.1
	B4GALNT1	NM_001413968.1		c.1569C>T	p.Asp523Asp	synonymous	Exon 11 of 11	NP_001400897.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B4GALNT1	ENST00000341156.9	TSL:1 MANE Select	c.1434C>T	p.Asp478Asp	synonymous	Exon 11 of 11	ENSP00000341562.4
	B4GALNT1	ENST00000418555.6	TSL:2	c.1269C>T	p.Asp423Asp	synonymous	Exon 10 of 10	ENSP00000401601.2
	B4GALNT1	ENST00000552468.1	TSL:2	n.1798C>T		non_coding_transcript_exon	Exon 2 of 2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461880 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112002

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia Benign:1

Apr 08, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	0.67
DANN	Benign	0.88
PhyloP100		-0.37

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1060504132; hg19: chr12-58020695;