chr16-29876927-G-A

Position:

• chr16-29876927-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001243332.2(SEZ6L2):​c.1933C>T​(p.Pro645Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SEZ6L2 NM_001243332.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.28

Genes affected

SEZ6L2 (HGNC:30844): (seizure related 6 homolog like 2) This gene encodes a seizure-related protein that is localized on the cell surface. The gene is located in a region of chromosome 16p11.2 that is thought to contain candidate genes for autism spectrum disorders (ASD), though there is no evidence directly implicating this gene in ASD. Increased expression of this gene has been found in lung cancers, and the protein is therefore considered to be a novel prognostic marker for lung cancer. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3955708).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SEZ6L2	NM_001243332.2	c.1933C>T	p.Pro645Ser	missense_variant	12/18	ENST00000617533.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SEZ6L2	ENST00000617533.5	c.1933C>T	p.Pro645Ser	missense_variant	12/18	1	NM_001243332.2	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1457664 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 724414

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 09, 2023

The c.1933C>T (p.P645S) alteration is located in exon 12 (coding exon 12) of the SEZ6L2 gene. This alteration results from a C to T substitution at nucleotide position 1933, causing the proline (P) at amino acid position 645 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.063	T
BayesDel_noAF	Benign	-0.33
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.12	.;.;T;.;.
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.94	D;D;D;D;D
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.40	T;T;T;T;T
MetaSVM	Benign	-0.73	T
MutationAssessor	Benign	1.5	.;.;L;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-1.6	N;N;N;N;.
REVEL	Benign	0.22
Sift	Benign	0.59	T;T;T;T;.
Sift4G	Benign	0.54	T;T;T;T;T
Polyphen		0.96, 0.81	.;D;P;.;.
Vest4		0.32
MutPred		0.75		.;.;Loss of glycosylation at P648 (P = 0.1345);.;Loss of glycosylation at P648 (P = 0.1345);
MVP		0.65
MPC		0.66
ClinPred		0.94	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.13
gMVP		0.54

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: rs776739626; hg19: chr16-29888248; COSMIC: COSV58099330;