rs376499974

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_005208.5(CRYBA1):​c.97-8C>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000406 in 1,478,232 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000038 ( 0 hom. )

Consequence

CRYBA1
NM_005208.5 splice_region, intron

Scores

2
Splicing: ADA: 0.1996
2

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 1.22

Publications

0 publications found
Variant links:
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: Labcorp Genetics (formerly Invitae), G2P, 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.36).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CRYBA1NM_005208.5 linkc.97-8C>A splice_region_variant, intron_variant Intron 2 of 5 ENST00000225387.8 NP_005199.2 P05813-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CRYBA1ENST00000225387.8 linkc.97-8C>A splice_region_variant, intron_variant Intron 2 of 5 1 NM_005208.5 ENSP00000225387.3 P05813-1
CRYBA1ENST00000484605.1 linkn.85-8C>A splice_region_variant, intron_variant Intron 2 of 4 5 ENSP00000464368.1 J3QRT1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
32
show subpopulations
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
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251486
AF XY:
0.00000736
show subpopulations
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:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000377
AC:
5
AN:
1326002
Hom.:
0
Cov.:
20
AF XY:
0.00000300
AC XY:
2
AN XY:
667366
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
30864
American (AMR)
AF:
0.00
AC:
0
AN:
44578
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25300
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39116
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83530
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53350
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5532
European-Non Finnish (NFE)
AF:
0.00000506
AC:
5
AN:
987870
Other (OTH)
AF:
0.00
AC:
0
AN:
55862
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000095), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68048
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.36
CADD
Benign
15
DANN
Benign
0.62
PhyloP100
1.2

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.20
dbscSNV1_RF
Benign
0.32
SpliceAI score (max)
0.23
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.23
Position offset: 26

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

Publications

Other links and lift over

dbSNP: rs376499974; hg19: chr17-27577192; API