chr2-201724392-G-A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_020919.4(ALS2):​c.3415C>T​(p.Arg1139*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000322 in 1,613,580 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

ALS2
NM_020919.4 stop_gained

Scores

5
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 5.57

Publications

1 publications found
Variant links:
Genes affected
ALS2 (HGNC:443): (alsin Rho guanine nucleotide exchange factor ALS2) The protein encoded by this gene contains an ATS1/RCC1-like domain, a RhoGEF domain, and a vacuolar protein sorting 9 (VPS9) domain, all of which are guanine-nucleotide exchange factors that activate members of the Ras superfamily of GTPases. The protein functions as a guanine nucleotide exchange factor for the small GTPase RAB5. The protein localizes with RAB5 on early endosomal compartments, and functions as a modulator for endosomal dynamics. Mutations in this gene result in several forms of juvenile lateral sclerosis and infantile-onset ascending spastic paralysis. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2008]
ALS2 Gene-Disease associations (from GenCC):
  • ALS2-related motor neuron disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • amyotrophic lateral sclerosis type 2, juvenile
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
  • infantile-onset ascending hereditary spastic paralysis
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
  • juvenile primary lateral sclerosis
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet
  • juvenile amyotrophic lateral sclerosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 2-201724392-G-A is Pathogenic according to our data. Variant chr2-201724392-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 393199.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALS2NM_020919.4 linkc.3415C>T p.Arg1139* stop_gained Exon 21 of 34 ENST00000264276.11 NP_065970.2 Q96Q42-1A8K4R4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALS2ENST00000264276.11 linkc.3415C>T p.Arg1139* stop_gained Exon 21 of 34 1 NM_020919.4 ENSP00000264276.6 Q96Q42-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152110
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000200
AC:
5
AN:
249496
AF XY:
0.0000222
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:
0.0000353
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000349
AC:
51
AN:
1461470
Hom.:
0
Cov.:
31
AF XY:
0.0000358
AC XY:
26
AN XY:
727068
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000414
AC:
46
AN:
1111660
Other (OTH)
AF:
0.00
AC:
0
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.444
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.00000657
AC:
1
AN:
152110
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74302
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41418
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.0000329
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Juvenile primary lateral sclerosis;C1859807:Amyotrophic lateral sclerosis type 2, juvenile;C2931441:Infantile-onset ascending hereditary spastic paralysis Pathogenic:1
Jul 21, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Mar 09, 2017
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Infantile-onset ascending hereditary spastic paralysis Pathogenic:1
May 11, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 393199). This premature translational stop signal has been observed in individual(s) with clinical features of leukodystrophy (PMID: 27159321). This variant is present in population databases (rs767350733, gnomAD 0.004%). This sequence change creates a premature translational stop signal (p.Arg1139*) in the ALS2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ALS2 are known to be pathogenic (PMID: 11586298, 24315819). -

Amyotrophic lateral sclerosis type 2, juvenile Pathogenic:1
Oct 23, 2018
Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The observed variant c.3415C>T (p.Arg1139Ter) has not been reported in 1000 Genomes and has a minor allele frequency of 0.002% in the ExAC databases. The in silico prediction of the given variant is damaging by MutationTaster2. -

not provided Pathogenic:1
Jan 31, 2017
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R1139X variant in the ALS2 gene has been reported previously in the compound heterozygous state, opposite of a second ALS2 variant, in two siblings with progressive spastic paraplegia, macrocephaly, speech and language delays, and abnormal findings on brain MRI (Vanderver et al., 2016). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The R1139X variant was not observed in approximately 6000 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Therefore, we interpret R1139X as a likely pathogenic variant. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.55
D
BayesDel_noAF
Pathogenic
0.65
CADD
Pathogenic
42
DANN
Uncertain
1.0
Eigen
Pathogenic
0.98
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
0.98
D
PhyloP100
5.6
Vest4
0.92
GERP RS
5.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=1/199
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs767350733; hg19: chr2-202589115; COSMIC: COSV105857898; COSMIC: COSV105857898; API