12-71138223-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004616.3(TSPAN8):c.269T>C(p.Ile90Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000616 in 1,461,120 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: TSPAN8 NM_004616.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.21

Genes affected

TSPAN8 (HGNC:11855): (tetraspanin 8) The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is a cell surface glycoprotein that is known to complex with integrins. This gene is expressed in different carcinomas. The use of alternate polyadenylation sites has been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.812

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSPAN8	NM_004616.3	c.269T>C	p.Ile90Thr	missense_variant	5/9	ENST00000247829.8
TSPAN8	NM_001369760.1	c.269T>C	p.Ile90Thr	missense_variant	4/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSPAN8	ENST00000247829.8	c.269T>C	p.Ile90Thr	missense_variant	5/9	1	NM_004616.3	P1
TSPAN8	ENST00000393330.6	c.269T>C	p.Ile90Thr	missense_variant	8/12	1		P1
TSPAN8	ENST00000546561.2	c.269T>C	p.Ile90Thr	missense_variant	4/8	1		P1
TSPAN8	ENST00000552128.2	n.133T>C		non_coding_transcript_exon_variant	2/6	3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461120 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 726930

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: 0.00000720

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

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

Nov 18, 2022

The c.269T>C (p.I90T) alteration is located in exon 5 (coding exon 4) of the TSPAN8 gene. This alteration results from a T to C substitution at nucleotide position 269, causing the isoleucine (I) at amino acid position 90 to be replaced by a threonine (T). 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	0.091
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Benign	-0.090
Cadd	Uncertain	24
Dann	Benign	0.97
DEOGEN2	Benign	0.17	T;T;T
Eigen	Uncertain	0.43
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.87	D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.81	D;D;D
MetaSVM	Uncertain	0.11	D
MutationAssessor	Uncertain	2.2	M;M;M
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Benign	0.42	T
PROVEAN	Uncertain	-2.9	D;D;D
REVEL	Uncertain	0.63
Sift	Uncertain	0.0050	D;D;D
Sift4G	Uncertain	0.014	D;D;D
Polyphen		1.0	D;D;D
Vest4		0.64
MutPred		0.70		Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);
MVP		0.63
MPC		0.52
ClinPred		0.95	D
GERP RS		4.2
Varity_R		0.58
gMVP		0.49

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs952846313; hg19: chr12-71532003;