rs878854979

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_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. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V171I) has been classified 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

Publications

1 publications found
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]
HSPB8 Gene-Disease associations (from GenCC):
  • neuronopathy, distal hereditary motor, autosomal dominant
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • Charcot-Marie-Tooth disease axonal type 2L
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • neuronopathy, distal hereditary motor, type 2A
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • autosomal dominant distal axonal motor neuropathy-myofibrillar myopathy syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • distal hereditary motor neuropathy type 2
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

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 rank MANE Protein UniProt
HSPB8NM_014365.3 linkc.512T>C p.Val171Ala missense_variant Exon 3 of 3 ENST00000281938.7 NP_055180.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HSPB8ENST00000281938.7 linkc.512T>C p.Val171Ala missense_variant Exon 3 of 3 1 NM_014365.3 ENSP00000281938.3

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
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251494
AF XY:
0.00000736
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 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
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.000246
AC:
11
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111980
Other (OTH)
AF:
0.000116
AC:
7
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
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
African (AFR)
AF:
0.00
AC:
0
AN:
41424
American (AMR)
AF:
0.000786
AC:
12
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68024
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
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
Nov 10, 2016
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Sep 19, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The 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
Jan 14, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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). This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with HSPB8-related conditions. ClinVar contains an entry for this variant (Variation ID: 240907). 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. 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. -

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
PhyloP100
4.8
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
Mutation Taster
=78/22
polymorphism

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

Other links and lift over

dbSNP: rs878854979; hg19: chr12-119631584; API