13-50910096-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_024570.4(RNASEH2B):c.20G>A(p.Cys7Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000114 in 1,463,690 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. C7C) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.00012 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00011 (0 hom.)
• Consequence: RNASEH2B NM_024570.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 0.755

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.057240963).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RNASEH2B	NM_024570.4	c.20G>A	p.Cys7Tyr	missense_variant	1/11	ENST00000336617.8
RNASEH2B-AS1	NR_046552.1	n.230+387C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RNASEH2B	ENST00000336617.8	c.20G>A	p.Cys7Tyr	missense_variant	1/11	1	NM_024570.4	P3
RNASEH2B-AS1	ENST00000596992.5	n.112+387C>T		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes AF: 0.000125 AC: 19 AN: 152040 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000785

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000883

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000118 AC: 8 AN: 67918 Hom.: 0 AF XY: 0.000102 AC XY: 4 AN XY: 39270

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000433

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000127

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000113 AC: 148 AN: 1311542 Hom.: 0 Cov.: 31 AF XY: 0.000110 AC XY: 71 AN XY: 645172

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000219

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: 0.000129

Gnomad4 OTH exome AF: 0.000148

GnomAD4 genome AF: 0.000125 AC: 19 AN: 152148 Hom.: 0 Cov.: 32 AF XY: 0.000108 AC XY: 8 AN XY: 74378

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.000784

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000883

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.000102

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Aicardi-Goutieres syndrome 2 Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 23, 2022	This sequence change replaces cysteine, which is neutral and slightly polar, with tyrosine, which is neutral and polar, at codon 7 of the RNASEH2B protein (p.Cys7Tyr). This variant is present in population databases (rs551573692, gnomAD 0.04%). 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: 881149). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Nov 03, 2021	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.27
Cadd	Benign	14
Dann	Uncertain	0.98
DEOGEN2	Benign	0.0053	T;.;.;.;.;.;.;.;.;.;.;.
Eigen	Benign	-0.81
Eigen_PC	Benign	-0.84
FATHMM_MKL	Benign	0.034	N
LIST_S2	Benign	0.76	T;T;T;T;T;T;T;T;T;T;T;T
M_CAP	Pathogenic	0.32	D
MetaRNN	Benign	0.057	T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.17	T
MutationAssessor	Benign	0.34	N;N;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Uncertain	0.65	T
PROVEAN	Benign	-0.32	N;N;.;.;.;.;.;.;.;.;.;.
REVEL	Benign	0.13
Sift	Benign	0.086	T;T;.;.;.;.;.;.;.;.;.;.
Sift4G	Benign	1.0	T;T;.;.;.;.;.;.;.;.;.;.
Polyphen		0.30	B;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.12
MutPred		0.42		Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);Gain of catalytic residue at V11 (P = 0);
MVP		0.60
MPC		0.075
ClinPred		0.054	T
GERP RS		1.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.5
Varity_R		0.21
gMVP		0.23

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

LitVar

Other links and lift over

dbSNP: rs551573692; hg19: chr13-51484232;