chr17-38762493-T-C

Position:

• chr17-38762493-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_002795.4(PSMB3):​c.557T>C​(p.Ile186Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,580 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: PSMB3 NM_002795.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.95

Genes affected

PSMB3 (HGNC:9540): (proteasome 20S subunit beta 3) The proteasome is a multicatalytic proteinase complex with a highly ordered ring-shaped 20S core structure. The core structure is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. This gene encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit. The 26 S proteasome may be involved in trinucleotide repeat expansion, a phenomenon which is associated with many hereditary neurological diseases. Pseudogenes have been identified on chromosomes 2 and 12. Alternative splicing results in multiple transcript variants [provided by RefSeq, Sep 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2721272).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PSMB3	NM_002795.4	c.557T>C	p.Ile186Thr	missense_variant	5/6	ENST00000619426.5
PSMB3	NR_104194.2	n.465T>C		non_coding_transcript_exon_variant	4/5
PSMB3	NR_104195.2	n.566T>C		non_coding_transcript_exon_variant	5/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PSMB3	ENST00000619426.5	c.557T>C	p.Ile186Thr	missense_variant	5/6	1	NM_002795.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461580 Hom.: 0 Cov.: 30 AF XY: 0.00000275 AC XY: 2 AN XY: 727122

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

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

Dec 04, 2023

The c.557T>C (p.I186T) alteration is located in exon 5 (coding exon 5) of the PSMB3 gene. This alteration results from a T to C substitution at nucleotide position 557, causing the isoleucine (I) at amino acid position 186 to be replaced by a threonine (T). 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	Benign	0.20
BayesDel_addAF	Uncertain	0.022	T
BayesDel_noAF	Benign	-0.21
CADD	Benign	22
DANN	Benign	0.97
DEOGEN2	Benign	0.076	T
Eigen	Benign	0.011
Eigen_PC	Benign	0.19
FATHMM_MKL	Uncertain	0.96	D
M_CAP	Benign	0.0041	T
MetaRNN	Benign	0.27	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.2	L
MutationTaster	Benign	0.98	D
PrimateAI	Uncertain	0.69	T
Sift4G	Benign	0.29	T
Polyphen		0.012	B
Vest4		0.56
MutPred		0.33		Gain of glycosylation at S181 (P = 0.1146);
MVP		0.10
ClinPred		0.91	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.26
gMVP		0.88

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: chr17-36918746;