Genetic Variant SMG6:p.Ala1339Thr (chr17-2065500-C-T) – ACMG Classification: Likely_benign (-6 pts)

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_017575.5(SMG6):c.4015G>A(p.Ala1339Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000124 in 1,613,324 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 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

SMG6
NM_017575.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.91

Variant links:

Genes affected

SMG6 (HGNC:17809): (SMG6 nonsense mediated mRNA decay factor) This gene encodes a component of the telomerase ribonucleoprotein complex responsible for the replication and maintenance of chromosome ends. The encoded protein also plays a role in the nonsense-mediated mRNA decay (NMD) pathway, providing the endonuclease activity near the premature translation termination codon that is needed to initiate NMD. Alternatively spliced transcript variants encoding distinct protein isoforms have been described. [provided by RefSeq, Feb 2014]

SMG6 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.23439416).

BS2

High AC in GnomAdExome4 at 19 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMG6	NM_017575.5 link	c.4015G>A	p.Ala1339Thr	missense_variant	Exon 17 of 19	ENST00000263073.11	NP_060045.4	Q86US8-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMG6	ENST00000263073.11 link	c.4015G>A	p.Ala1339Thr	missense_variant	Exon 17 of 19	1	NM_017575.5	ENSP00000263073.5		Q86US8-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152198

Hom.:

Cov.:

show subpopulations

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:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

250800

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135572

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461126

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

726874

show subpopulations

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:

0.0000116

Gnomad4 FIN exome

AF:

0.0000376

Gnomad4 NFE exome

AF:

0.0000144

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152198

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74346

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Feb 22, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.4015G>A (p.A1339T) alteration is located in exon 17 (coding exon 17) of the SMG6 gene. This alteration results from a G to A substitution at nucleotide position 4015, causing the alanine (A) at amino acid position 1339 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

Pathogenic

0.71

BayesDel_addAF

Benign

-0.17

BayesDel_noAF

Benign

-0.41

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.025

T;.;.

Eigen

Uncertain

0.39

Eigen_PC

Uncertain

0.47

FATHMM_MKL

Uncertain

0.87

LIST_S2

Uncertain

0.93

D;.;D

M_CAP

Benign

0.012

MetaRNN

Benign

0.23

T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.3

L;.;.

PrimateAI

Uncertain

0.71

PROVEAN

Benign

-0.19

N;.;N

REVEL

Benign

0.098

Sift

Benign

0.32

T;.;T

Sift4G

Benign

0.30

T;T;T

Polyphen

0.99

D;.;.

Vest4

0.40

MutPred

0.34

Loss of helix (P = 0.028);.;.;

MVP

0.34

MPC

0.54

ClinPred

0.70

GERP RS

5.6

Varity_R

0.28

gMVP

0.37

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over