5-151267479-C-A

Variant names:

• chr5-151267479-C-A
• rs9324685
• NM_000405.5:c.*28C>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000405.5(GM2A):​c.*28C>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,594 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: GM2A NM_000405.5 3_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.35
• Publications: 0 publications found

Genes affected

GM2A (HGNC:4367): (ganglioside GM2 activator) This gene encodes a small glycolipid transport protein which acts as a substrate specific co-factor for the lysosomal enzyme beta-hexosaminidase A. Beta-hexosaminidase A, together with GM2 ganglioside activator, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. Mutations in this gene result in GM2-gangliosidosis type AB or the AB variant of Tay-Sachs disease. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2009]

GM2A Gene-Disease associations (from GenCC):

• Tay-Sachs disease AB variant

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GM2A	NM_000405.5	c.*28C>A		3_prime_UTR_variant	Exon 4 of 4	ENST00000357164.4	NP_000396.2
GM2A	NM_001167607.3	c.413-13C>A		intron_variant	Intron 3 of 3		NP_001161079.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GM2A	ENST00000357164.4	c.*28C>A		3_prime_UTR_variant	Exon 4 of 4	1	NM_000405.5	ENSP00000349687.3
GM2A	ENST00000523004.1	c.*554C>A		downstream_gene_variant		1		ENSP00000430541.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461594 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727096

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44700

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86220

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53362

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111864

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	19
DANN	Benign	0.49
PhyloP100		1.4

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.57		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.57		Position offset: 1

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

Other links and lift over

dbSNP: rs9324685; hg19: chr5-150647040;