2-201700649-G-A

Variant names:

• chr2-201700649-G-A
• rs41309068
• NM_020919.4:c.*1202C>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Moderate BP6_Moderate BS1 BS2

The NM_020919.4(ALS2):​c.*1202C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00339 in 152,288 control chromosomes in the GnomAD database, including 9 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★).

• Frequency:
  • Genomes: 𝑓 0.0034 (9 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: ALS2 NM_020919.4 3_prime_UTR
• Clinical Significance: Benign criteria provided, single submitter B:2
• Conservation: PhyloP100: 1.86
• Publications: 1 publications found

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

ACMG classification

Our verdict: Benign. The variant received -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.23).
• BP6: Variant 2-201700649-G-A is Benign according to our data. Variant chr2-201700649-G-A is described in ClinVar as [Benign]. Clinvar id is 333572.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.00339 (516/152288) while in subpopulation AMR AF = 0.0277 (424/15292). AF 95% confidence interval is 0.0255. There are 9 homozygotes in GnomAd4. There are 301 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 9 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ALS2	NM_020919.4	c.*1202C>T		3_prime_UTR_variant	Exon 34 of 34	ENST00000264276.11	NP_065970.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ALS2	ENST00000264276.11	c.*1202C>T		3_prime_UTR_variant	Exon 34 of 34	1	NM_020919.4	ENSP00000264276.6

Frequencies

GnomAD3 genomes AF: 0.00338 AC: 515 AN: 152170 Hom.: 9 Cov.: 32

Gnomad AFR AF: 0.000700

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0277

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00924

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000735

Gnomad OTH AF: 0.00382

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 434 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 262

African (AFR) AC: 0 AN: 0

American (AMR) AC: 0 AN: 0

Ashkenazi Jewish (ASJ) AC: 0 AN: 0

East Asian (EAS) AF: 0.00 AC: 0 AN: 2

South Asian (SAS) AC: 0 AN: 0

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 426

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 2

Other (OTH) AF: 0.00 AC: 0 AN: 4

GnomAD4 genome AF: 0.00339 AC: 516 AN: 152288 Hom.: 9 Cov.: 32 AF XY: 0.00404 AC XY: 301 AN XY: 74472

African (AFR) AF: 0.000698 AC: 29 AN: 41570

American (AMR) AF: 0.0277 AC: 424 AN: 15292

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00926 AC: 48 AN: 5184

South Asian (SAS) AF: 0.000414 AC: 2 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10604

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000735 AC: 5 AN: 68020

Other (OTH) AF: 0.00378 AC: 8 AN: 2114

Alfa AF: 0.00270 Hom.: 0

Bravo AF: 0.00518

Asia WGS AF: 0.00318 AC: 11 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, single submitter

Submissions by phenotype

Amyotrophic lateral sclerosis type 2, juvenile Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

ALS2-related disorder Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.23
CADD	Benign	14
DANN	Benign	0.68
PhyloP100		1.9

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: rs41309068; hg19: chr2-202565372;