Genetic Variant NHP2:p.His132GlnfsTer30 (chr5-178149779-A-ATGGGGCTT) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_017838.4(NHP2):c.388_395dupAAGCCCCA(p.His132GlnfsTer30) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.000042 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

NHP2
NM_017838.4 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.94

Variant links:

Genes affected

NHP2 (HGNC:14377): (NHP2 ribonucleoprotein) This gene is a member of the H/ACA snoRNPs (small nucleolar ribonucleoproteins) gene family. snoRNPs are involved in various aspects of rRNA processing and modification and have been classified into two families: C/D and H/ACA. The H/ACA snoRNPs also include the DKC1, NOLA1 and NOLA3 proteins. These four H/ACA snoRNP proteins localize to the dense fibrillar components of nucleoli and to coiled (Cajal) bodies in the nucleus. Both 18S rRNA production and rRNA pseudouridylation are impaired if any one of the four proteins is depleted. The four H/ACA snoRNP proteins are also components of the telomerase complex. This gene encodes a protein related to Saccharomyces cerevisiae Nhp2p. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2008]

NHP2 links:

RMND5B (HGNC:26181): (required for meiotic nuclear division 5 homolog B) Predicted to enable metal ion binding activity and ubiquitin protein ligase activity. Predicted to contribute to ubiquitin-protein transferase activity. Predicted to be involved in proteasome-mediated ubiquitin-dependent protein catabolic process. Located in cytosol. [provided by Alliance of Genome Resources, Apr 2022]

RMND5B links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NHP2	NM_017838.4 link	c.388_395dupAAGCCCCA	p.His132GlnfsTer30	frameshift_variant	Exon 4 of 4	ENST00000274606.8	NP_060308.1	Q9NX24
RMND5B	NM_022762.5 link	c.1748_1755dupTGGGGCTT		3_prime_UTR_variant	Exon 11 of 11	ENST00000313386.9	NP_073599.2	Q96G75-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NHP2	ENST00000274606.8 link	c.388_395dupAAGCCCCA	p.His132GlnfsTer30	frameshift_variant	Exon 4 of 4	1	NM_017838.4	ENSP00000274606.4		Q9NX24
RMND5B	ENST00000313386.9 link	c.1748_1755dupTGGGGCTT		3_prime_UTR_variant	Exon 11 of 11	1	NM_022762.5	ENSP00000320623.4		Q96G75-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

251214

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135768

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

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:

0.0000616

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

Data not reliable, filtered out with message: AS_VQSR

AF:

0.0000424

AC:

AN:

1461764

Hom.:

Cov.:

AF XY:

0.0000344

AC XY:

AN XY:

727176

show subpopulations

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:

0.0000549

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Dyskeratosis congenita

Uncertain:1

Jan 22, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. This variant has not been reported in the literature in individuals with NHP2-related disease. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the ExAC database. This sequence change results in a premature translational stop signal in the NHP2 gene (p.His132Glnfs*30). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 22 amino acids of the NHP2 protein. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

Splicing

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over