22-26599551-C-A

Variant names:

• chr22-26599551-C-A
• rs575368335
• NM_001887.4:c.698G>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PM5

The NM_001887.4(CRYBB1):​c.698G>T​(p.Arg233Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000656 in 152,364 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R233C) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: CRYBB1 NM_001887.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.76
• Publications: 10 publications found

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]

CRYBA4 (HGNC:2396): (crystallin beta A4) 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 acidic group member, is part of a gene cluster with beta-B1, beta-B2, and beta-B3. [provided by RefSeq, Jul 2008]

CRYBA4 Gene-Disease associations (from GenCC):

• cataract 23

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• cataract - microcornea syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• early-onset lamellar cataract

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000286326 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr22-26599551-C-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2737022.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001887.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRYBB1	NM_001887.4	MANE Select	c.698G>T	p.Arg233Leu	missense	Exon 6 of 6	NP_001878.1	P53674

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRYBB1	ENST00000647684.1	MANE Select	c.698G>T	p.Arg233Leu	missense	Exon 6 of 6	ENSP00000497249.1	P53674
	CRYBB1	ENST00000872124.1		c.698G>T	p.Arg233Leu	missense	Exon 6 of 6	ENSP00000542183.1
	CRYBB1	ENST00000872125.1		c.698G>T	p.Arg233Leu	missense	Exon 6 of 6	ENSP00000542184.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152246 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251188 AF XY: 0.00000736

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000656 AC: 1 AN: 152364 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74518

African (AFR) AF: 0.00 AC: 0 AN: 41590

American (AMR) AF: 0.00 AC: 0 AN: 15310

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2116

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.32
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.25
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.26	T
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Uncertain	0.11	D
MetaRNN	Uncertain	0.72	D
MetaSVM	Uncertain	0.062	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		3.8
PrimateAI	Benign	0.43	T
PROVEAN	Pathogenic	-5.2	D
REVEL	Uncertain	0.64
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0060	D
Polyphen		0.98	D
Vest4		0.82
MutPred		0.50		Loss of MoRF binding (P = 0.0219)
MVP		0.89
MPC		0.75
ClinPred		0.99	D
GERP RS		4.2
Varity_R		0.83
gMVP		0.63
Mutation Taster		=31/69	disease causing

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

Other links and lift over

dbSNP: rs575368335; hg19: chr22-26995515;