chr7-100646293-G-A

Variant names:

• chr7-100646293-G-A
• NM_016188.5:c.1156C>T

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PP2 PP3_Strong

The NM_016188.5(ACTL6B):​c.1156C>T​(p.Arg386Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,850 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R386H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: ACTL6B NM_016188.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.96
• Publications: 0 publications found

Genes affected

ACTL6B (HGNC:160): (actin like 6B) The protein encoded by this gene is a member of a family of actin-related proteins (ARPs) which share significant amino acid sequence identity to conventional actins. Both actins and ARPs have an actin fold, which is an ATP-binding cleft, as a common feature. The ARPs are involved in diverse cellular processes, including vesicular transport, spindle orientation, nuclear migration and chromatin remodeling. This gene encodes a subunit of the BAF (BRG1/brm-associated factor) complex in mammals, which is functionally related to SWI/SNF complex in S. cerevisiae and Drosophila; the latter is thought to facilitate transcriptional activation of specific genes by antagonizing chromatin-mediated transcriptional repression. This subunit may be involved in the regulation of genes by structural modulation of their chromatin, specifically in the brain. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]

ACTL6B Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 76

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• intellectual developmental disorder with severe speech and ambulation defects

  Inheritance: AD Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PP2: Missense variant in the ACTL6B gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 18 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 3.2738 (above the threshold of 3.09). Trascript score misZ: 3.3665 (above the threshold of 3.09). GenCC associations: The gene is linked to intellectual developmental disorder with severe speech and ambulation defects, syndromic intellectual disability, developmental and epileptic encephalopathy, 76, undetermined early-onset epileptic encephalopathy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_016188.5. 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
	ACTL6B	NM_016188.5	MANE Select	c.1156C>T	p.Arg386Cys	missense	Exon 13 of 14	NP_057272.1	O94805
	ACTL6B	NR_134539.2		n.1267C>T		non_coding_transcript_exon	Exon 13 of 14

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTL6B	ENST00000160382.10	TSL:1 MANE Select	c.1156C>T	p.Arg386Cys	missense	Exon 13 of 14	ENSP00000160382.5	O94805
	ACTL6B	ENST00000970942.1		c.1225C>T	p.Arg409Cys	missense	Exon 14 of 15	ENSP00000641001.1
	ACTL6B	ENST00000863236.1		c.889C>T	p.Arg297Cys	missense	Exon 11 of 12	ENSP00000533295.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461850 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727216

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

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

European-Non Finnish (NFE) AF: 0.00000719 AC: 8 AN: 1111998

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	ACTL6B-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.28	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		3.0
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.4	D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.92		Gain of catalytic residue at M384 (P = 0)
MVP		0.96
MPC		2.5
ClinPred		1.0	D
GERP RS		3.7
Varity_R		0.82
gMVP		0.91
Mutation Taster		=45/55	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.11		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

hg19: chr7-100243916; COSMIC: COSV50514372; COSMIC: COSV50514372;