2-201718172-A-T

Variant names:

• chr2-201718172-A-T
• NM_020919.4:c.3741T>A
• ALS2 p.Gly1247Gly

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_020919.4(ALS2):​c.3741T>A​(p.Gly1247Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G1247G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: ALS2 NM_020919.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.0120
• Publications: 0 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: Orphanet, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• juvenile primary lateral sclerosis

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• juvenile amyotrophic lateral sclerosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.59).
• BP7: Synonymous conserved (PhyloP=-0.012 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020919.4. 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
	ALS2	NM_020919.4	MANE Select	c.3741T>A	p.Gly1247Gly	synonymous	Exon 24 of 34	NP_065970.2
	ALS2	NM_001410975.1		c.3741T>A	p.Gly1247Gly	synonymous	Exon 24 of 34	NP_001397904.1	A0A7P0T8F3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALS2	ENST00000264276.11	TSL:1 MANE Select	c.3741T>A	p.Gly1247Gly	synonymous	Exon 24 of 34	ENSP00000264276.6	Q96Q42-1
	ALS2	ENST00000680497.1		c.3843T>A	p.Gly1281Gly	synonymous	Exon 24 of 34	ENSP00000505954.1	A0A7P0Z4F3
	ALS2	ENST00000905985.1		c.3834T>A	p.Gly1278Gly	synonymous	Exon 25 of 35	ENSP00000576044.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	4.0
DANN	Benign	0.71
PhyloP100		-0.012
Mutation Taster		=98/2	polymorphism

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr2-202582895;