22-25202714-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_004076.5(CRYBB3):c.116G>T(p.Cys39Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000185 in 1,461,792 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000018 (0 hom.)
• Consequence: CRYBB3 NM_004076.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.324

Genes affected

CRYBB3 (HGNC:2400): (crystallin beta B3) 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-B2. Mutations in this gene result in cataract congenital nuclear autosomal recessive type 2. [provided by RefSeq, Feb 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.27917188).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CRYBB3	NM_004076.5	c.116G>T	p.Cys39Phe	missense_variant	3/6	ENST00000215855.7
CRYBB3	XM_047441147.1	c.116G>T	p.Cys39Phe	missense_variant	2/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CRYBB3	ENST00000215855.7	c.116G>T	p.Cys39Phe	missense_variant	3/6	1	NM_004076.5	P1
CRYBB3	ENST00000404334.1	c.116G>T	p.Cys39Phe	missense_variant	3/5	3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251378 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135908

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000185 AC: 27 AN: 1461792 Hom.: 0 Cov.: 32 AF XY: 0.0000193 AC XY: 14 AN XY: 727196

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.0000243

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Jun 01, 2018

- -

Cataract 22 multiple types Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

MGZ Medical Genetics Center

Jan 27, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.062	T
BayesDel_noAF	Benign	-0.31
Cadd	Benign	14
Dann	Benign	0.80
DEOGEN2	Benign	0.10	T;T
Eigen	Benign	-0.28
Eigen_PC	Benign	-0.30
FATHMM_MKL	Benign	0.26	N
LIST_S2	Benign	0.36	T;T
M_CAP	Benign	0.026	D
MetaRNN	Benign	0.28	T;T
MetaSVM	Benign	-0.48	T
MutationAssessor	Benign	0.73	N;.
MutationTaster	Benign	0.99	D;D
PrimateAI	Uncertain	0.51	T
PROVEAN	Uncertain	-2.5	D;D
REVEL	Benign	0.26
Sift	Benign	0.69	T;T
Sift4G	Benign	0.62	T;T
Polyphen		0.35	B;.
Vest4		0.42
MutPred		0.48		Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);
MVP		0.82
MPC		0.25
ClinPred		0.16	T
GERP RS		2.3
Varity_R		0.36
gMVP		0.46

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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

Other links and lift over

dbSNP: rs1232309133; hg19: chr22-25598681; COSMIC: COSV53195117;