rs1264025914

Variant names:

• chr17-29250301-G-A
• rs1264025914
• NM_005208.5:c.215+1G>A

Your query was ambiguous. Multiple possible variants found:

• chr17-29250301-G-A
• chr17-29250301-G-C
• chr17-29250301-G-T

Variant summary

Our verdict is Pathogenic. The variant received 22 ACMG points: 22P and 0B. PVS1 PS3 PM2 PP5_Very_Strong

The NM_005208.5(CRYBA1):​c.215+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000254 in 1,573,234 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV001759095: "In vitro functional studies show that the c.215+1G>A variant causes a splice defect in which the mutant mRNA skips both exons 3 and 4, escaping nonsense-mediated mRNA decay. Skipping these exons results in an in-frame deletion of the mRNA and synthesis of an unstable protein." PMID:26851658" and additional evidence is available in ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CRYBA1 NM_005208.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 9.27
• Publications: 7 publications found

Genes affected

CRYBA1 (HGNC:2394): (crystallin beta A1) 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, encodes two proteins (crystallin, beta A3 and crystallin, beta A1) from a single mRNA, the latter protein is 17 aa shorter than crystallin, beta A3 and is generated by use of an alternate translation initiation site. Deletion of exons 3 and 4 causes the autosomal dominant disease 'zonular cataract with sutural opacities'. [provided by RefSeq, Jul 2008]

CRYBA1 Gene-Disease associations (from GenCC):

• cataract 10 multiple types

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• early-onset lamellar cataract

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

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

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 22 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV001759095: "In vitro functional studies show that the c.215+1G>A variant causes a splice defect in which the mutant mRNA skips both exons 3 and 4, escaping nonsense-mediated mRNA decay. Skipping these exons results in an in-frame deletion of the mRNA and synthesis of an unstable protein." PMID:26851658; SCV004709532: Functional studies have shown that this variant leads to skipping of both exons 3 and 4 and results in the formation of an unstable βA3/A1-crystallin protein (Ma et al. 2016. PubMed ID: 26851658).
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-29250301-G-A is Pathogenic according to our data. Variant chr17-29250301-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 521851.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005208.5. 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
	CRYBA1	NM_005208.5	MANE Select	c.215+1G>A		splice_donor intron	N/A	NP_005199.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRYBA1	ENST00000225387.8	TSL:1 MANE Select	c.215+1G>A		splice_donor intron	N/A	ENSP00000225387.3	P05813-1
	CRYBA1	ENST00000484605.1	TSL:5	n.203+1G>A		splice_donor intron	N/A	ENSP00000464368.1	J3QRT1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152188 Hom.: 0 Cov.: 32

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000211 AC: 3 AN: 1421046 Hom.: 0 Cov.: 25 AF XY: 0.00000282 AC XY: 2 AN XY: 709554

African (AFR) AF: 0.00 AC: 0 AN: 32688

American (AMR) AF: 0.00 AC: 0 AN: 44676

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25896

East Asian (EAS) AF: 0.00 AC: 0 AN: 39536

South Asian (SAS) AF: 0.00 AC: 0 AN: 85490

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53398

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5670

European-Non Finnish (NFE) AF: 0.00000279 AC: 3 AN: 1074586

Other (OTH) AF: 0.00 AC: 0 AN: 59106

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152188 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74346

African (AFR) AF: 0.00 AC: 0 AN: 41434

American (AMR) AF: 0.00 AC: 0 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10618

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
5	-	-	Cataract 10 multiple types (5)
1	-	-	CRYBA1-related disorder (1)
1	-	-	Inborn genetic diseases (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.3
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.98		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs1264025914; hg19: chr17-27577319; COSMIC: COSV56601116;