1-2228776-G-C

Position:

• chr1-2228776-G-C

Variant summary

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

The NM_003036.4(SKI):​c.10G>C​(p.Ala4Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000088 in 1,136,708 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A4V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 8.8e-7 (0 hom.)
• Consequence: SKI NM_003036.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.91

Genes affected

SKI (HGNC:10896): (SKI proto-oncogene) This gene encodes the nuclear protooncogene protein homolog of avian sarcoma viral (v-ski) oncogene. It functions as a repressor of TGF-beta signaling, and may play a role in neural tube development and muscle differentiation. [provided by RefSeq, Oct 2009]

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=0.32006314).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SKI	NM_003036.4	c.10G>C	p.Ala4Pro	missense_variant	1/7	ENST00000378536.5
SKI	XM_005244775.4	c.10G>C	p.Ala4Pro	missense_variant	1/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SKI	ENST00000378536.5	c.10G>C	p.Ala4Pro	missense_variant	1/7	1	NM_003036.4	P1
SKI	ENST00000704337.1	n.137+1252G>C		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 8.80e-7 AC: 1 AN: 1136708 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 557264

Gnomad4 AFR exome AF: 0.0000435

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.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Shprintzen-Goldberg syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 14, 2020

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. This variant has not been reported in the literature in individuals with SKI-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SKI protein function. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This sequence change replaces alanine with proline at codon 4 of the SKI protein (p.Ala4Pro). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.077	D
BayesDel_noAF	Benign	-0.13
CADD	Benign	22
DANN	Benign	0.95
DEOGEN2	Benign	0.21	T
Eigen	Benign	-0.75
Eigen_PC	Benign	-0.83
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.54	T
M_CAP	Pathogenic	0.97	D
MetaRNN	Benign	0.32	T
MetaSVM	Uncertain	-0.018	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	0.83	N
PrimateAI	Pathogenic	0.88	D
PROVEAN	Benign	-0.16	N
REVEL	Uncertain	0.31
Sift	Benign	0.10	T
Sift4G	Benign	0.23	T
Polyphen		0.49	P
Vest4		0.35
MutPred		0.30		Gain of loop (P = 0.024);
MVP		0.68
MPC		1.8
ClinPred		0.16	T
Varity_R		0.21
gMVP		0.26

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: rs1638560343; hg19: chr1-2160215;