2-238848375-G-T

Variant names:

• chr2-238848375-G-T
• rs1458958603
• NM_001271893.4:c.160G>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_001271893.4(TWIST2):​c.160G>T​(p.Gly54Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,292 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G54S) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: TWIST2 NM_001271893.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.576
• Publications: 0 publications found

Genes affected

TWIST2 (HGNC:20670): (twist family bHLH transcription factor 2) The protein encoded by this gene is a basic helix-loop-helix type transcription factor and shares similarity with Twist. This protein may inhibit osteoblast maturation and maintain cells in a preosteoblast phenotype during osteoblast development. This gene may be upregulated in certain cancers. Mutations in this gene cause focal facial dermal dysplasia 3, Setleis type. Two transcript variants encoding the same protein have been found. [provided by RefSeq, Apr 2014]

TWIST2 Gene-Disease associations (from GenCC):

• ablepharon macrostomia syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet
• Barber-Say syndrome

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• focal facial dermal dysplasia type III

  Inheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 3 curated pathogenic missense variants (we use a threshold of 10). The gene has 0 curated benign missense variants. Gene score misZ: 2.1324 (below the threshold of 3.09). Trascript score misZ: 0.22546 (below the threshold of 3.09). GenCC associations: The gene is linked to Barber-Say syndrome, ablepharon macrostomia syndrome, focal facial dermal dysplasia type III.
• BP4: Computational evidence support a benign effect (MetaRNN=0.19307119).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001271893.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWIST2	NM_001271893.4	MANE Select	c.160G>T	p.Gly54Cys	missense	Exon 1 of 2	NP_001258822.1	Q8WVJ9
	TWIST2	NM_057179.3		c.160G>T	p.Gly54Cys	missense	Exon 1 of 2	NP_476527.1	Q8WVJ9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWIST2	ENST00000612363.2	TSL:1 MANE Select	c.160G>T	p.Gly54Cys	missense	Exon 1 of 2	ENSP00000482581.1	Q8WVJ9
	TWIST2	ENST00000448943.2	TSL:1	c.160G>T	p.Gly54Cys	missense	Exon 1 of 2	ENSP00000405176.2	Q8WVJ9
	TWIST2	ENST00000710607.1		c.160G>T	p.Gly54Cys	missense	Exon 1 of 2	ENSP00000518373.1	Q8WVJ9

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152174 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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.000478

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152292 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74472

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41576

American (AMR) AF: 0.00 AC: 0 AN: 15306

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5158

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68020

Other (OTH) AF: 0.000473 AC: 1 AN: 2114

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.075
BayesDel_addAF	Uncertain	0.062	T
BayesDel_noAF	Benign	-0.15
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.11	T
Eigen	Benign	0.017
Eigen_PC	Benign	0.14
FATHMM_MKL	Benign	0.45	N
LIST_S2	Benign	0.84	T
M_CAP	Uncertain	0.26	D
MetaRNN	Benign	0.19	T
MetaSVM	Uncertain	0.60	D
MutationAssessor	Benign	-0.69	N
PhyloP100		0.58
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-0.90	N
REVEL	Uncertain	0.37
Sift	Benign	0.14	T
Sift4G	Uncertain	0.047	D
Polyphen		0.95	P
Vest4		0.12
MutPred		0.25		Gain of methylation at K53 (P = 0.0316)
MVP		0.98
MPC		2.3
ClinPred		0.74	D
GERP RS		4.8
PromoterAI		-0.13	Neutral
Varity_R		0.16
gMVP		0.47
Mutation Taster		=72/28	polymorphism

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

Other links and lift over

dbSNP: rs1458958603; hg19: chr2-239757016;