rs146763276

Positions:

chr22-25227921-G-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM1BP4BS2

The NM_000496.3(CRYBB2):c.242G>A(p.Arg81His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000229 in 1,614,118 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: 𝑓 0.000099 ( 0 hom., cov: 28)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

CRYBB2
NM_000496.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.38

Variant links:

Genes affected

CRYBB2 (HGNC:2398): (crystallin beta B2) 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, is part of a gene cluster with beta-A4, beta-B1, and beta-B3. A chain-terminating mutation was found to cause type 2 cerulean cataracts. [provided by RefSeq, Jul 2008]

CRYBB2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM1

In a chain Beta-crystallin B2 (size 203) in uniprot entity CRBB2_HUMAN there are 36 pathogenic changes around while only 2 benign (95%) in NM_000496.3

BP4

Computational evidence support a benign effect (MetaRNN=0.3955272).

BS2

High AC in GnomAd4 at 15 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CRYBB2	NM_000496.3 linkuse as main transcript	c.242G>A	p.Arg81His	missense_variant	4/6	ENST00000398215.3
CRYBB2	XM_006724141.4 linkuse as main transcript	c.242G>A	p.Arg81His	missense_variant	4/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CRYBB2	ENST00000398215.3 linkuse as main transcript	c.242G>A	p.Arg81His	missense_variant	4/6	1	NM_000496.3	P1
CRYBB2	ENST00000651629.1 linkuse as main transcript	c.242G>A	p.Arg81His	missense_variant	4/6			P1

Frequencies

GnomAD3 genomes

AF:

0.0000986

AC:

AN:

152120

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000338

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000398

AC:

AN:

251380

Hom.:

AF XY:

0.0000515

AC XY:

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.000308

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000653

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000150

AC:

AN:

1461880

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.0000896

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000135

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000985

AC:

AN:

152238

Hom.:

Cov.:

AF XY:

0.000107

AC XY:

AN XY:

74434

show subpopulations

Gnomad4 AFR

AF:

0.000337

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000614

Hom.:

Bravo

AF:

0.0000642

ESP6500AA

AF:

0.000454

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000494

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Cataract 3 multiple types

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 01, 2022

This variant has not been reported in the literature in individuals affected with CRYBB2-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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25"). ClinVar contains an entry for this variant (Variation ID: 463970). This variant is present in population databases (rs146763276, gnomAD 0.05%), and has an allele count higher than expected for a pathogenic variant. This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 81 of the CRYBB2 protein (p.Arg81His). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.56

BayesDel_addAF

Benign

-0.19

BayesDel_noAF

Benign

-0.13

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.44

Eigen

Uncertain

0.36

Eigen_PC

Uncertain

0.35

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

0.98

M_CAP

Benign

0.031

MetaRNN

Benign

0.40

MetaSVM

Uncertain

-0.15

MutationAssessor

Benign

1.8

MutationTaster

Benign

1.0

PrimateAI

Pathogenic

0.88

PROVEAN

Uncertain

-4.4

REVEL

Pathogenic

0.68

Sift

Benign

0.039

Sift4G

Benign

0.18

Polyphen

1.0

Vest4

0.36

MVP

0.71

MPC

0.64

ClinPred

0.25

GERP RS

4.1

Varity_R

0.52

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.050

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over