7-19116759-G-C

Variant names:

• chr7-19116759-G-C
• rs121909191
• NM_000474.4:c.563C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_000474.4(TWIST1):​c.563C>G​(p.Ser188Trp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,956 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. S188L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TWIST1 NM_000474.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.83
• Publications: 6 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: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a chain Twist-related protein 1 (size 201) in uniprot entity TWST1_HUMAN there are 39 pathogenic changes around while only 6 benign (87%) in NM_000474.4
• 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 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, 0.927

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.563C>G	p.Ser188Trp	missense	Exon 1 of 2	NP_000465.1
	TWIST1	NR_149001.2		n.878C>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.563C>G	p.Ser188Trp	missense	Exon 1 of 2	ENSP00000242261.5
	TWIST1	ENST00000354571.5	TSL:2	n.359C>G		non_coding_transcript_exon	Exon 1 of 3	ENSP00000346582.5
	TWIST1	ENST00000443687.5	TSL:4	n.164C>G		non_coding_transcript_exon	Exon 1 of 4	ENSP00000416986.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000404 AC: 1 AN: 247634 AF XY: 0.00000745

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.000100

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460956 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726690

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44630

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26108

East Asian (EAS) AF: 0.00 AC: 0 AN: 39656

South Asian (SAS) AF: 0.00 AC: 0 AN: 86064

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53230

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111678

Other (OTH) AF: 0.00 AC: 0 AN: 60358

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	34
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.80	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		9.8
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-7.0	D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.82
MutPred		0.56		Gain of MoRF binding (P = 0.0442)
MVP		1.0
MPC		3.1
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.91
gMVP		0.93
Mutation Taster		=39/61	disease causing

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: rs121909191; hg19: chr7-19156382;