rs104894059

Variant names:

• chr7-19116856-T-C
• rs104894059
• NM_000474.4:c.466A>G

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000474.4(TWIST1):​c.466A>G​(p.Ile156Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I156S) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TWIST1 NM_000474.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.88
• Publications: 4 publications found

Genes affected

TWIST1 (HGNC:12428): (twist family bHLH transcription factor 1) This gene encodes a basic helix-loop-helix (bHLH) transcription factor that plays an important role in embryonic development. The encoded protein forms both homodimers and heterodimers that bind to DNA E box sequences and regulate the transcription of genes involved in cranial suture closure during skull development. This protein may also regulate neural tube closure, limb development and brown fat metabolism. This gene is hypermethylated and overexpressed in multiple human cancers, and the encoded protein promotes tumor cell invasion and metastasis, as well as metastatic recurrence. Mutations in this gene cause Saethre-Chotzen syndrome in human patients, which is characterized by craniosynostosis, ptosis and hypertelorism. [provided by RefSeq, Jul 2020]

TWIST1 Gene-Disease associations (from GenCC):

• Saethre-Chotzen syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, PanelApp Australia, Laboratory for Molecular Medicine, ClinGen, Orphanet, Labcorp Genetics (formerly Invitae)
• TWIST1-related craniosynostosis

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• isolated brachycephaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• isolated plagiocephaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• isolated scaphocephaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Sweeney-Cox syndrome

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 19 ACMG points.

• PM1: In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000474.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-19116855-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 1455499.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 31 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 1.057 (below the threshold of 3.09). Trascript score misZ: -0.22696 (below the threshold of 3.09). GenCC associations: The gene is linked to Saethre-Chotzen syndrome, Sweeney-Cox syndrome, isolated brachycephaly, TWIST1-related craniosynostosis, isolated plagiocephaly, isolated scaphocephaly.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.973
• PP5: Variant 7-19116856-T-C is Pathogenic according to our data. Variant chr7-19116856-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 7982.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000474.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWIST1	NM_000474.4	MANE Select	c.466A>G	p.Ile156Val	missense	Exon 1 of 2	NP_000465.1
	TWIST1	NR_149001.2		n.781A>G		non_coding_transcript_exon	Exon 1 of 3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWIST1	ENST00000242261.6	TSL:1 MANE Select	c.466A>G	p.Ile156Val	missense	Exon 1 of 2	ENSP00000242261.5
	TWIST1	ENST00000354571.5	TSL:2	n.262A>G		non_coding_transcript_exon	Exon 1 of 3	ENSP00000346582.5
	TWIST1	ENST00000443687.5	TSL:4	n.67A>G		non_coding_transcript_exon	Exon 1 of 4	ENSP00000416986.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Saethre-Chotzen syndrome (2)
1	-	-	Saethre-Chotzen syndrome;C4551902:TWIST1-related craniosynostosis (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Pathogenic	2.9	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.84	D
PROVEAN	Benign	-1.0	N
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0060	D
Polyphen		1.0	D
Vest4		0.92
MutPred		0.80		Gain of MoRF binding (P = 0.1613)
MVP		1.0
MPC		2.4
ClinPred		0.98	D
GERP RS		4.8
Varity_R		0.69
gMVP		0.97
Mutation Taster		=14/86	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.31		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.31		Position offset: 5

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs104894059; hg19: chr7-19156479;