1-35883445-A-T

Position:

• chr1-35883445-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_012199.5(AGO1):​c.24A>T​(p.Ala8=) variant causes a splice region, 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. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: AGO1 NM_012199.5 splice_region, synonymous
• Scores: Splicing: ADA: 0.9991
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.61

Genes affected

AGO1 (HGNC:3262): (argonaute RISC component 1) This gene encodes a member of the argonaute family of proteins, which associate with small RNAs and have important roles in RNA interference (RNAi) and RNA silencing. This protein binds to microRNAs (miRNAs) or small interfering RNAs (siRNAs) and represses translation of mRNAs that are complementary to them. It is also involved in transcriptional gene silencing (TGS) of promoter regions that are complementary to bound short antigene RNAs (agRNAs), as well as in the degradation of miRNA-bound mRNA targets. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. A recent study showed this gene to be an authentic stop codon readthrough target, and that its mRNA could give rise to an additional C-terminally extended isoform by use of an alternative in-frame translation termination codon. [provided by RefSeq, Nov 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AGO1	NM_012199.5	c.24A>T	p.Ala8=	splice_region_variant, synonymous_variant	1/19	ENST00000373204.6	NP_036331.1
AGO1	NM_001317122.2	c.24A>T	p.Ala8=	splice_region_variant, synonymous_variant	1/19		NP_001304051.1
AGO1	XM_011541236.3	c.24A>T	p.Ala8=	splice_region_variant, synonymous_variant	1/19		XP_011539538.1
AGO1	NM_001317123.2	c.-200-4982A>T		intron_variant			NP_001304052.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AGO1	ENST00000373204.6	c.24A>T	p.Ala8=	splice_region_variant, synonymous_variant	1/19	1	NM_012199.5	ENSP00000362300	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 01, 2024

Variant summary: AGO1 c.24A>T (p.Ala8Ala) alters a conserved nucleotide in the last nucleotide of exon 1 adjacent to the exon 1/intron 1 5' splice donor site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Several computational tools predict a significant impact on normal splicing: Three predict the variant weakens a 5' donor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 195376 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.24A>T in individuals affected with Neurodevelopmental Disorder With Language Delay And Behavioral Abnormalities, With Or Without Seizures and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.40
CADD	Benign	23
DANN	Benign	0.93
RBP_binding_hub_radar		1.1
RBP_regulation_power_radar		3.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.83
SpliceAI score (max)		0.38		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.38		Position offset: -33

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-36349046;