20-20026904-A-T

Position:

• chr20-20026904-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_016100.5(NAA20):​c.290A>T​(p.Glu97Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: NAA20 NM_016100.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.50

Genes affected

NAA20 (HGNC:15908): (N-alpha-acetyltransferase 20, NatB catalytic subunit) NAT5 is a component of N-acetyltransferase complex B (NatB). Human NatB performs cotranslational N(alpha)-terminal acetylation of methionine residues when they are followed by asparagine (Starheim et al., 2008 [PubMed 18570629]).[supplied by OMIM, Apr 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a domain N-acetyltransferase (size 155) in uniprot entity NAA20_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_016100.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.83

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NAA20	NM_016100.5	c.290A>T	p.Glu97Val	missense_variant	4/6	ENST00000334982.9
NAA20	NM_181527.3	c.254A>T	p.Glu85Val	missense_variant	4/6
NAA20	NM_181528.3	c.290A>T	p.Glu97Val	missense_variant	4/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NAA20	ENST00000334982.9	c.290A>T	p.Glu97Val	missense_variant	4/6	1	NM_016100.5	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

Ambry Genetics

Nov 09, 2021

The c.290A>T (p.E97V) alteration is located in exon 4 (coding exon 4) of the NAA20 gene. This alteration results from a A to T substitution at nucleotide position 290, causing the glutamic acid (E) at amino acid position 97 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Benign	0.23	T;.;T
Eigen	Pathogenic	0.72
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.83	D;D;D
MetaSVM	Benign	-0.76	T
MutationAssessor	Uncertain	2.0	M;M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-7.0	D;D;D
REVEL	Uncertain	0.44
Sift	Uncertain	0.025	D;D;D
Sift4G	Uncertain	0.0090	D;D;D
Polyphen		0.87	P;.;D
Vest4		0.79
MutPred		0.56		Loss of disorder (P = 0.0023);Loss of disorder (P = 0.0023);.;
MVP		0.67
MPC		1.4
ClinPred		0.99	D
GERP RS		5.4
Varity_R		0.75
gMVP		0.82

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: chr20-20007548;