chr12-119193779-T-C

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM1BP4_ModerateBS2

The NM_014365.3(HSPB8):​c.512T>C​(p.Val171Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000192 in 1,613,998 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 (★★).

Frequency

Genomes: 𝑓 0.000085 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

HSPB8
NM_014365.3 missense

Scores

3
16

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 4.82
Variant links:
Genes affected
HSPB8 (HGNC:30171): (heat shock protein family B (small) member 8) The protein encoded by this gene belongs to the superfamily of small heat-shock proteins containing a conservative alpha-crystallin domain at the C-terminal part of the molecule. The expression of this gene in induced by estrogen in estrogen receptor-positive breast cancer cells, and this protein also functions as a chaperone in association with Bag3, a stimulator of macroautophagy. Thus, this gene appears to be involved in regulation of cell proliferation, apoptosis, and carcinogenesis, and mutations in this gene have been associated with different neuromuscular diseases, including Charcot-Marie-Tooth disease. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

PM1
In a domain sHSP (size 111) in uniprot entity HSPB8_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_014365.3
BP4
Computational evidence support a benign effect (MetaRNN=0.12949735).
BS2
High AC in GnomAd4 at 13 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
HSPB8NM_014365.3 linkuse as main transcriptc.512T>C p.Val171Ala missense_variant 3/3 ENST00000281938.7 NP_055180.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
HSPB8ENST00000281938.7 linkuse as main transcriptc.512T>C p.Val171Ala missense_variant 3/31 NM_014365.3 ENSP00000281938 P1

Frequencies

GnomAD3 genomes
AF:
0.0000854
AC:
13
AN:
152144
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000786
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:
0.00
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251494
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135920
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000123
AC:
18
AN:
1461854
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727228
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000246
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:
0.00
Gnomad4 OTH exome
AF:
0.000116
GnomAD4 genome
AF:
0.0000854
AC:
13
AN:
152144
Hom.:
0
Cov.:
32
AF XY:
0.0000807
AC XY:
6
AN XY:
74328
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000786
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.000478
Bravo
AF:
0.000257

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesNov 10, 2016- -
Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsSep 19, 2023The c.512T>C (p.V171A) alteration is located in exon 3 (coding exon 3) of the HSPB8 gene. This alteration results from a T to C substitution at nucleotide position 512, causing the valine (V) at amino acid position 171 to be replaced by an alanine (A). The alteration is rare in population databases: _x000D_ _x000D_ Based on data from the Genome Aggregation Database (gnomAD), the c.512T>C alteration was observed in <0.001% (1/251,494) of total alleles studied. The altered amino acid is not conserved throughout evolution:_x000D_ _x000D_ The p.V171 amino acid is not conserved in available vertebrate species. The alteration is predicted tolerated by in silico modeling:_x000D_ _x000D_ The p.V171A alteration is predicted to be tolerated by in silico analysis. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Charcot-Marie-Tooth disease axonal type 2L Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJun 29, 2023In 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. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 240907). This variant has not been reported in the literature in individuals affected with HSPB8-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.006%). This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 171 of the HSPB8 protein (p.Val171Ala). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.34
BayesDel_addAF
Benign
-0.067
T
BayesDel_noAF
Benign
-0.16
CADD
Benign
21
DANN
Benign
0.96
DEOGEN2
Benign
0.35
T
Eigen
Benign
-0.29
Eigen_PC
Benign
-0.18
FATHMM_MKL
Benign
0.75
D
LIST_S2
Benign
0.83
T
M_CAP
Benign
0.039
D
MetaRNN
Benign
0.13
T
MetaSVM
Uncertain
-0.26
T
MutationAssessor
Benign
1.2
L
MutationTaster
Benign
0.77
N
PrimateAI
Uncertain
0.53
T
PROVEAN
Benign
-0.45
N
REVEL
Benign
0.20
Sift
Benign
0.24
T
Sift4G
Benign
0.82
T
Polyphen
0.12
B
Vest4
0.19
MutPred
0.42
Gain of catalytic residue at P172 (P = 2e-04);
MVP
0.94
MPC
0.30
ClinPred
0.23
T
GERP RS
3.3
Varity_R
0.035
gMVP
0.32

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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

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

Other links and lift over

dbSNP: rs878854979; hg19: chr12-119631584; API