rs777225392

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM1BP4BS2

The NM_001540.5(HSPB1):​c.554T>C​(p.Phe185Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,262 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. F185L) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

HSPB1
NM_001540.5 missense

Scores

2
6
11

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.75

Publications

1 publications found
Variant links:
Genes affected
HSPB1 (HGNC:5246): (heat shock protein family B (small) member 1) This gene encodes a member of the small heat shock protein (HSP20) family of proteins. In response to environmental stress, the encoded protein translocates from the cytoplasm to the nucleus and functions as a molecular chaperone that promotes the correct folding of other proteins. This protein plays an important role in the differentiation of a wide variety of cell types. Expression of this gene is correlated with poor clinical outcome in multiple human cancers, and the encoded protein may promote cancer cell proliferation and metastasis, while protecting cancer cells from apoptosis. Mutations in this gene have been identified in human patients with Charcot-Marie-Tooth disease and distal hereditary motor neuropathy. [provided by RefSeq, Aug 2017]
HSPB1 Gene-Disease associations (from GenCC):
  • Charcot-Marie-Tooth disease axonal type 2F
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Illumina, Labcorp Genetics (formerly Invitae)
  • neuronopathy, distal hereditary motor, type 2B
    Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
  • 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 -3 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 17 uncertain in NM_001540.5
BP4
Computational evidence support a benign effect (MetaRNN=0.32943946).
BS2
High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HSPB1NM_001540.5 linkc.554T>C p.Phe185Ser missense_variant Exon 3 of 3 ENST00000248553.7 NP_001531.1 P04792V9HW43

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HSPB1ENST00000248553.7 linkc.554T>C p.Phe185Ser missense_variant Exon 3 of 3 1 NM_001540.5 ENSP00000248553.6 P04792

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000405
AC:
1
AN:
246762
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000902
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000821
AC:
12
AN:
1461262
Hom.:
0
Cov.:
33
AF XY:
0.00000550
AC XY:
4
AN XY:
726898
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33456
American (AMR)
AF:
0.00
AC:
0
AN:
44684
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86194
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53216
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5744
European-Non Finnish (NFE)
AF:
0.0000108
AC:
12
AN:
1111818
Other (OTH)
AF:
0.00
AC:
0
AN:
60340
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
3
4
5
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
Cov.:
32
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease axonal type 2F Uncertain:1
Jun 09, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This sequence change replaces phenylalanine with serine at codon 185 of the HSPB1 protein (p.Phe185Ser). The phenylalanine residue is moderately conserved and there is a large physicochemical difference between phenylalanine and serine. 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 variant has not been reported in the literature in individuals with a HSPB1-related disease. In summary, this variant has uncertain impact on HSPB1 function. The available evidence is currently insufficient to determine its role 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
Pathogenic
0.71
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Uncertain
0.060
CADD
Benign
18
DANN
Benign
0.97
DEOGEN2
Benign
0.37
T;T
Eigen
Benign
-0.47
Eigen_PC
Benign
-0.42
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Benign
0.79
T;T
M_CAP
Uncertain
0.28
D
MetaRNN
Benign
0.33
T;T
MetaSVM
Uncertain
0.44
D
MutationAssessor
Benign
1.8
L;.
PhyloP100
2.7
PrimateAI
Uncertain
0.52
T
PROVEAN
Benign
-2.1
N;D
REVEL
Uncertain
0.43
Sift
Benign
0.38
T;D
Sift4G
Benign
0.88
T;D
Polyphen
0.39
B;.
Vest4
0.37
MutPred
0.27
Gain of phosphorylation at F185 (P = 0.0373);.;
MVP
1.0
MPC
1.1
ClinPred
0.15
T
GERP RS
3.5
Varity_R
0.41
gMVP
0.66
Mutation Taster
=77/23
polymorphism

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

Other links and lift over

dbSNP: rs777225392; hg19: chr7-75933426; API