rs754348253

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2BP4_ModerateBP6_ModerateBP7

The NM_001101426.4(CRPPA):​c.816G>T​(p.Ala272Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,534 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 Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. A272A) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CRPPA
NM_001101426.4 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: -1.19

Publications

0 publications found
Variant links:
Genes affected
CRPPA (HGNC:37276): (CDP-L-ribitol pyrophosphorylase A) This gene encodes a 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase-like protein. Mutations in this gene are the cause of Walker-Warburg syndrome. Alternate splicing results in multiple transcript variants. [provided by RefSeq, May 2012]
CRPPA Gene-Disease associations (from GenCC):
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • myopathy caused by variation in CRPPA
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • autosomal recessive limb-girdle muscular dystrophy type 2U
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital muscular dystrophy without intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscular dystrophy-dystroglycanopathy, type A
    Inheritance: AR 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 -3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.28).
BP6
Variant 7-16301440-C-A is Benign according to our data. Variant chr7-16301440-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 1680766.Status of the report is criteria_provided_single_submitter, 1 stars.
BP7
Synonymous conserved (PhyloP=-1.19 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CRPPANM_001101426.4 linkc.816G>T p.Ala272Ala synonymous_variant Exon 5 of 10 ENST00000407010.7 NP_001094896.1 A4D126-1
CRPPANM_001368197.1 linkc.711G>T p.Ala237Ala synonymous_variant Exon 4 of 9 NP_001355126.1
CRPPANM_001101417.4 linkc.666G>T p.Ala222Ala synonymous_variant Exon 4 of 9 NP_001094887.1 A4D126-2A0A140VJM1
CRPPANR_160656.1 linkn.901-23214G>T intron_variant Intron 3 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CRPPAENST00000407010.7 linkc.816G>T p.Ala272Ala synonymous_variant Exon 5 of 10 5 NM_001101426.4 ENSP00000385478.2 A4D126-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000403
AC:
1
AN:
248094
AF XY:
0.00000743
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000291
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
AF:
6.85e-7
AC:
1
AN:
1460534
Hom.:
0
Cov.:
29
AF XY:
0.00000138
AC XY:
1
AN XY:
726488
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:
33474
American (AMR)
AF:
0.0000224
AC:
1
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39660
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85910
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53382
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111220
Other (OTH)
AF:
0.00
AC:
0
AN:
60326
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), 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
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7;C5190987:Autosomal recessive limb-girdle muscular dystrophy type 2U Benign:1
May 31, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.28
CADD
Benign
3.3
DANN
Benign
0.64
PhyloP100
-1.2

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

Other links and lift over

dbSNP: rs754348253; hg19: chr7-16341065; API