3-32106712-A-G

Position:

• chr3-32106712-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 8P and 4B. PVS1 BS2

The NM_015141.4(GPD1L):​c.1A>G​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000576 in 1,562,704 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 Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000050 (0 hom.)
• Consequence: GPD1L NM_015141.4 start_lost
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.09

Genes affected

GPD1L (HGNC:28956): (glycerol-3-phosphate dehydrogenase 1 like) The protein encoded by this gene catalyzes the conversion of sn-glycerol 3-phosphate to glycerone phosphate. The encoded protein is found in the cytoplasm, associated with the plasma membrane, where it binds the sodium channel, voltage-gated, type V, alpha subunit (SCN5A). Defects in this gene are a cause of Brugada syndrome type 2 (BRS2) as well as sudden infant death syndrome (SIDS). [provided by RefSeq, Jul 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• BS2: High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GPD1L	NM_015141.4	c.1A>G	p.Met1?	start_lost	1/8	ENST00000282541.10	NP_055956.1
GPD1L	XM_006713068.3	c.1A>G	p.Met1?	start_lost	1/7		XP_006713131.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GPD1L	ENST00000282541.10	c.1A>G	p.Met1?	start_lost	1/8	1	NM_015141.4	ENSP00000282541	P1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152040 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000496 AC: 7 AN: 1410556 Hom.: 0 Cov.: 30 AF XY: 0.00000428 AC XY: 3 AN XY: 701430

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000247

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000460

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152148 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74398

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000118 AC: 1

ExAC AF: 0.00000834 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Aug 16, 2019

Has not been previously published as pathogenic or benign to our knowledge; Not observed in large population cohorts (Lek et al., 2016); Initiation codon variant in a gene for which loss-of-function is not a known mechanism of disease -

Brugada syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 25, 2021

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant has not been reported in the literature in individuals affected with GPD1L-related conditions. This variant is present in population databases (rs148643167, gnomAD 0.004%). This sequence change affects the initiator methionine of the GPD1L mRNA. The next in-frame methionine is located at codon 40. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 06, 2019

The p.M1? variant (also known as c.1A>G), located in coding exon 1 of the GPD1L gene, results from an A to G substitution at nucleotide position 1. This alters the methionine residue at the initiation codon. This alteration is expected to modify the initiation codon (ATG) resulting in either loss of translation initiation, N-terminal truncation, or cause a shift in the mRNA reading frame. However, loss of function of GPD1L has not been clearly established as a mechanism of disease. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.11
CADD	Benign	23
DANN	Benign	0.97
DEOGEN2	Benign	0.11	T;.
Eigen	Benign	-0.16
Eigen_PC	Benign	-0.015
FATHMM_MKL	Benign	0.45	N
LIST_S2	Uncertain	0.90	D;D
M_CAP	Pathogenic	0.99	D
MetaRNN	Benign	0.39	T;T
MetaSVM	Benign	-1.0	T
MutationTaster	Benign	1.0	D
PROVEAN	Benign	-0.46	N;N
REVEL	Benign	0.21
Sift	Benign	0.23	T;T
Sift4G	Benign	0.16	T;T
Polyphen		0.0010	B;.
Vest4		0.82
MVP		0.64
ClinPred		0.89	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.14
gMVP		0.68

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

Publications

LitVar

Other links and lift over

dbSNP: rs148643167; hg19: chr3-32148204;