chr13-50910078-TG-T

Variant names:

• chr13-50910078-TG-T
• NM_024570.4:c.4delG

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_024570.4(RNASEH2B):​c.4delG​(p.Ala2ProfsTer23) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000763 in 1,311,206 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.6e-7 (0 hom.)
• Consequence: RNASEH2B NM_024570.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.31

Genes affected

RNASEH2B (HGNC:25671): (ribonuclease H2 subunit B) RNase H2 is composed of a single catalytic subunit (A) and two non-catalytic subunits (B and C) and specifically degrades the RNA of RNA:DNA hybrids. The protein encoded by this gene is the non-catalytic B subunit of RNase H2, which is thought to play a role in DNA replication. Multiple transcript variants encoding different isoforms have been found for this gene. Defects in this gene are a cause of Aicardi-Goutieres syndrome type 2 (AGS2). [provided by RefSeq, Nov 2008]

RNASEH2B-AS1 (HGNC:39967): (RNASEH2B antisense RNA 1)

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 44 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 13-50910078-TG-T is Pathogenic according to our data. Variant chr13-50910078-TG-T is described in ClinVar as [Pathogenic]. Clinvar id is 1451439.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RNASEH2B	NM_024570.4	c.4delG	p.Ala2ProfsTer23	frameshift_variant	Exon 1 of 11	ENST00000336617.8	NP_078846.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RNASEH2B	ENST00000336617.8	c.4delG	p.Ala2ProfsTer23	frameshift_variant	Exon 1 of 11	1	NM_024570.4	ENSP00000337623.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.63e-7 AC: 1 AN: 1311206 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 645210

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.58e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Aicardi-Goutieres syndrome 2 Pathogenic:1

Aug 31, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ala2Profs*23) in the RNASEH2B gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in RNASEH2B are known to be pathogenic (PMID: 17846997). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with RNASEH2B-related conditions. ClinVar contains an entry for this variant (Variation ID: 1451439). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr13-51484214;