3-33093495-T-A

Variant names:

• chr3-33093495-T-A
• rs372500334
• NM_001039770.3:c.701A>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001039770.3(TMPPE):​c.701A>T​(p.Asn234Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,892 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N234T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TMPPE NM_001039770.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.37
• Publications: 0 publications found

Genes affected

TMPPE (HGNC:33865): (transmembrane protein with metallophosphoesterase domain) Predicted to enable hydrolase activity and metal ion binding activity. Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

GLB1 (HGNC:4298): (galactosidase beta 1) This gene encodes a member of the glycosyl hydrolase 35 family of proteins. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate the mature lysosomal enzyme. This enzyme catalyzes the hydrolysis of a terminal beta-linked galactose residue from ganglioside substrates and other glycoconjugates. Mutations in this gene may result in GM1-gangliosidosis and Morquio B syndrome. [provided by RefSeq, Nov 2015]

GLB1 Gene-Disease associations (from GenCC):

• GM1 gangliosidosis

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Myriad Women’s Health
• GM1 gangliosidosis type 3

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• mucopolysaccharidosis type 4B

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp
• GM1 gangliosidosis type 1

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• GM1 gangliosidosis type 2

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001039770.3. 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
	TMPPE	NM_001039770.3	MANE Select	c.701A>T	p.Asn234Ile	missense	Exon 2 of 2	NP_001034859.2	Q6ZT21-1
	GLB1	NM_000404.4	MANE Select	c.75+3516A>T		intron	N/A	NP_000395.3
	TMPPE	NM_001136238.2		c.290A>T	p.Asn97Ile	missense	Exon 2 of 2	NP_001129710.1	Q6ZT21-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TMPPE	ENST00000342462.5	TSL:2 MANE Select	c.701A>T	p.Asn234Ile	missense	Exon 2 of 2	ENSP00000343398.4	Q6ZT21-1
	GLB1	ENST00000307363.10	TSL:1 MANE Select	c.75+3516A>T		intron	N/A	ENSP00000306920.4	P16278
	GLB1	ENST00000307377.12	TSL:1	c.75+3516A>T		intron	N/A	ENSP00000305920.8	E7EQ29

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461892 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727248

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112012

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Uncertain	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.70	D
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.89	D
M_CAP	Uncertain	0.18	D
MetaRNN	Uncertain	0.73	D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Pathogenic	3.3	M
PhyloP100		6.4
PrimateAI	Uncertain	0.50	T
PROVEAN	Pathogenic	-8.5	D
REVEL	Uncertain	0.58
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.32
MutPred		0.71		Gain of catalytic residue at V235 (P = 0.1019)
MVP		0.68
MPC		1.2
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.63
gMVP		0.86
Mutation Taster		=65/35	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: rs372500334; hg19: chr3-33134987;