chr22-26601942-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001887.4(CRYBB1):​c.512C>T​(p.Ala171Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000403 in 1,613,190 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

CRYBB1
NM_001887.4 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.72
Variant links:
Genes affected
CRYBB1 (HGNC:2397): (crystallin beta B1) Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins. Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and gamma crystallins are also considered as a superfamily. Alpha and beta families are further divided into acidic and basic groups. Seven protein regions exist in crystallins: four homologous motifs, a connecting peptide, and N- and C-terminal extensions. Beta-crystallins, the most heterogeneous, differ by the presence of the C-terminal extension (present in the basic group, none in the acidic group). Beta-crystallins form aggregates of different sizes and are able to self-associate to form dimers or to form heterodimers with other beta-crystallins. This gene, a beta basic group member, undergoes extensive cleavage at its N-terminal extension during lens maturation. It is also a member of a gene cluster with beta-A4, beta-B2, and beta-B3. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.025810778).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CRYBB1NM_001887.4 linkuse as main transcriptc.512C>T p.Ala171Val missense_variant 5/6 ENST00000647684.1 NP_001878.1
CRYBB1XM_011529899.4 linkuse as main transcriptc.512C>T p.Ala171Val missense_variant 5/6 XP_011528201.1
CRYBA4XM_006724140.4 linkuse as main transcriptc.-239+4859G>A intron_variant XP_006724203.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CRYBB1ENST00000647684.1 linkuse as main transcriptc.512C>T p.Ala171Val missense_variant 5/6 NM_001887.4 ENSP00000497249 P1
ENST00000668614.1 linkuse as main transcriptn.56+4859G>A intron_variant, non_coding_transcript_variant
CRYBB1ENST00000647569.1 linkuse as main transcript downstream_gene_variant

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152148
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00
GnomAD3 exomes
AF:
0.000255
AC:
64
AN:
251314
Hom.:
0
AF XY:
0.000199
AC XY:
27
AN XY:
135810
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00182
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:
0.000163
GnomAD4 exome
AF:
0.0000431
AC:
63
AN:
1461042
Hom.:
0
Cov.:
32
AF XY:
0.0000344
AC XY:
25
AN XY:
726836
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00141
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:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152148
Hom.:
0
Cov.:
31
AF XY:
0.0000269
AC XY:
2
AN XY:
74328
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000131
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:
0.00
Alfa
AF:
0.000142
Hom.:
0
Bravo
AF:
0.0000756
ExAC
AF:
0.000247
AC:
30

ClinVar

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

Submissions by phenotype

Cataract 17 multiple types Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpMar 13, 2022This variant is present in population databases (rs753533677, gnomAD 0.2%). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 171 of the CRYBB1 protein (p.Ala171Val). This variant has not been reported in the literature in individuals affected with CRYBB1-related conditions. 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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.051
BayesDel_addAF
Benign
-0.51
T
BayesDel_noAF
Benign
-0.51
CADD
Benign
7.3
DANN
Benign
0.23
DEOGEN2
Benign
0.10
T;T
Eigen
Benign
-1.1
Eigen_PC
Benign
-0.82
FATHMM_MKL
Benign
0.29
N
LIST_S2
Uncertain
0.86
.;D
M_CAP
Benign
0.0061
T
MetaRNN
Benign
0.026
T;T
MetaSVM
Benign
-0.93
T
MutationAssessor
Benign
-2.0
N;N
MutationTaster
Benign
0.98
N
PrimateAI
Benign
0.27
T
PROVEAN
Benign
3.1
.;N
REVEL
Benign
0.16
Sift
Benign
1.0
.;T
Sift4G
Benign
1.0
.;T
Polyphen
0.0020
B;B
Vest4
0.28
MutPred
0.65
Loss of catalytic residue at A171 (P = 0.0676);Loss of catalytic residue at A171 (P = 0.0676);
MVP
0.66
MPC
0.32
ClinPred
0.023
T
GERP RS
3.8
Varity_R
0.11
gMVP
0.25

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

LitVar

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

Other links and lift over

dbSNP: rs753533677; hg19: chr22-26997906; API