rs281875326

Positions:

• chr17-81511526-G-A

Variant summary

Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PM1 PM2 PP2 PP3_Moderate PP5_Very_Strong

The NM_001614.5(ACTG1):​c.464C>T​(p.Ser155Phe) 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. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ACTG1 NM_001614.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5 O:1
• Conservation: PhyloP100: 9.50

Genes affected

ACTG1 (HGNC:144): (actin gamma 1) Actins are highly conserved proteins that are involved in various types of cell motility and in maintenance of the cytoskeleton. Three main groups of actin isoforms have been identified in vertebrate animals: alpha, beta, and gamma. The alpha actins are found in muscle tissues and are a major constituent of the contractile apparatus. The beta and gamma actins co-exist in most cell types as components of the cytoskeleton and as mediators of internal cell motility. Actin gamma 1, encoded by this gene, is a cytoplasmic actin found in all cell types. Mutations in this gene are associated with DFNA20/26, a subtype of autosomal dominant non-syndromic sensorineural progressive hearing loss and also with Baraitser-Winter syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2017]

ACMG classification

Verdict is Pathogenic. Variant got 15 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_001614.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, ACTG1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.93
• PP5: Variant 17-81511526-G-A is Pathogenic according to our data. Variant chr17-81511526-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 29585.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-81511526-G-A is described in Lovd as [Pathogenic]. Variant chr17-81511526-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACTG1	NM_001614.5	c.464C>T	p.Ser155Phe	missense_variant	4/6	ENST00000573283.7
ACTG1	NM_001199954.3	c.464C>T	p.Ser155Phe	missense_variant	4/6
ACTG1	NR_037688.3	n.536C>T		non_coding_transcript_exon_variant	4/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACTG1	ENST00000573283.7	c.464C>T	p.Ser155Phe	missense_variant	4/6	5	NM_001614.5	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Baraitser-winter syndrome 2 Pathogenic:2

Pathogenic, no assertion criteria provided	literature only	OMIM	Feb 26, 2012	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Sep 25, 2013	- -

not provided Pathogenic:1 Other:1

not provided, no classification provided	literature only	UniProtKB/Swiss-Prot	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Oct 05, 2022	Not observed at significant frequency in large population cohorts (gnomAD); Missense variants in this gene are often considered pathogenic (HGMD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 28496999, 32506774, 35054877, 27096712, 24268205, 29620237, 32349449, 28439872, 29372643, 28493397, 22366783, 27240540, 30143558) -

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 17, 2023

The c.464C>T (p.S155F) alteration is located in exon 4 (coding exon 3) of the ACTG1 gene. This alteration results from a C to T substitution at nucleotide position 464, causing the serine (S) at amino acid position 155 to be replaced by a phenylalanine (F)._x000D_ _x000D_ for Baraitser-Winter syndrome; however, its clinical significance for ACTG1-related deafness is uncertain. This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This alteration has been reported in multiple individuals with features consistent with Baraitser-Winter syndrome, including two de novo occurrences (Rivière, 2012). This amino acid position is highly conserved in available vertebrate species. A functional analysis of the p.S155F alteration demonstrated increased F-actin content and multiple anomalous F-actin rich filopodia-like protrusions compared to control cells (Rivière, 2012). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Congenital anomaly of kidney and urinary tract Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

Yale Center for Mendelian Genomics, Yale University

Aug 24, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;D;D;D;D;D;D;D;D;D;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.93	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.4	H;H;H;H;H;H;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.80	T
Sift4G	Uncertain	0.021	D;D;D;D;D;.;.;.;D;D;D
Polyphen		1.0	D;D;D;D;D;D;.;.;.;.;.
Vest4		0.95
MutPred		0.54		Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);.;Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);Loss of disorder (P = 0.0018);.;
MVP		0.99
ClinPred		1.0	D
GERP RS		4.6
Varity_R		0.98
gMVP		0.99

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: rs281875326; hg19: chr17-79478552;