rs372686280

Variant summary

Our verdict is Pathogenic. The variant received 8 ACMG points: 8P and 0B. PM3_StrongPVS1_Strong

This summary comes from the ClinGen Evidence Repository: The variant c.990+1G>T in ACTA1 occurs within the canonical splice donor site (+1) of intron 6. It is predicted to cause skipping of biologically-relevant-exon resulting in an out of frame deletion. However, it is predicted to escape nonsense mediated decay and remove >10% of the protein (PVS1_Strong). The highest minor allele frequency in gnomAD v4.1.0 is 0.00001883 (31/1180028 alleles) in the European (non-Finnish) population (no population codes met). This variant has been reported in trans with a pathogenic variant in two probands with nemaline myopathy (PMID:19562689, LOVD (https://www.dmd.nl/)), and homozygous in one proband with nemaline myopathy (https://helda.helsinki.fi/handle/10138/157180) which meets PM3_Strong. In summary, the variant meets the criteria to be classified as pathogenic for autosomal recessive alpha-actinopathy. ACMG/AMP criteria met, as specified by the ClinGen Congenital Myopathies VCEP: PVS1_Strong, PM3_Strong (ClinGen Congenital Myopathies VCEP specifications version 1; 08/07/2024). LINK:https://erepo.genome.network/evrepo/ui/classification/CA1442746/MONDO:0100084/169

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

ACTA1
NM_001100.4 splice_donor, intron

Scores

4
2
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic reviewed by expert panel P:5

Conservation

PhyloP100: 7.68

Publications

1 publications found
Variant links:
Genes affected
ACTA1 (HGNC:129): (actin alpha 1, skeletal muscle) The product encoded by this gene belongs to the actin family of proteins, which are highly conserved proteins that play a role in cell motility, structure and integrity. Alpha, beta and gamma actin isoforms have been identified, with alpha actins being a major constituent of the contractile apparatus, while beta and gamma actins are involved in the regulation of cell motility. This actin is an alpha actin that is found in skeletal muscle. Mutations in this gene cause a variety of myopathies, including nemaline myopathy, congenital myopathy with excess of thin myofilaments, congenital myopathy with cores, and congenital myopathy with fiber-type disproportion, diseases that lead to muscle fiber defects with manifestations such as hypotonia. [provided by RefSeq, Sep 2019]
ACTA1 Gene-Disease associations (from GenCC):
  • alpha-actinopathy
    Inheritance: AR, AD Classification: DEFINITIVE Submitted by: ClinGen
  • congenital myopathy 2a, typical, autosomal dominant
    Inheritance: AR, SD, AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • congenital myopathy with excess of thin filaments
    Inheritance: SD Classification: DEFINITIVE Submitted by: Illumina
  • congenital myopathy 2c, severe infantile, autosomal dominant
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • childhood-onset nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital fiber-type disproportion myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • intermediate nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • progressive scapulohumeroperoneal distal myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • typical nemaline myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • rigid spine syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • severe congenital nemaline myopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • zebra body myopathy
    Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 8 ACMG points.

PVS1
For more information check the summary or visit ClinGen Evidence Repository.
PM3
For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001100.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ACTA1
NM_001100.4
MANE Select
c.990+1G>T
splice_donor intron
N/ANP_001091.1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ACTA1
ENST00000366684.7
TSL:1 MANE Select
c.990+1G>T
splice_donor intron
N/AENSP00000355645.3
ACTA1
ENST00000871224.1
c.990+1G>T
splice_donor intron
N/AENSP00000541283.1
ACTA1
ENST00000871225.1
c.990+1G>T
splice_donor intron
N/AENSP00000541284.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152204
Hom.:
0
Cov.:
32
show subpopulations
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251344
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461862
Hom.:
0
Cov.:
31
AF XY:
0.0000220
AC XY:
16
AN XY:
727236
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000252
AC:
28
AN:
1111996
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
3
6
10
13
16
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152204
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74352
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.0000189
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

ClinVar submissions as Germline
Significance:Pathogenic
Revision:reviewed by expert panel
View on ClinVar
Pathogenic
VUS
Benign
Condition
2
-
-
Actin accumulation myopathy (2)
2
-
-
not provided (2)
1
-
-
Alpha-actinopathy (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.59
D
BayesDel_noAF
Pathogenic
0.24
CADD
Pathogenic
36
DANN
Uncertain
0.99
Eigen
Pathogenic
0.95
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Uncertain
0.96
D
PhyloP100
7.7
GERP RS
3.6
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
1.0
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.72
Position offset: 2
DS_DL_spliceai
1.0
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs372686280; hg19: chr1-229567467; API