rs397515398

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PM4_SupportingPP5

The NM_001101426.4(CRPPA):​c.277_279delATT​(p.Ile93del) variant causes a conservative inframe deletion change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000235 in 1,613,598 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

CRPPA
NM_001101426.4 conservative_inframe_deletion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 8.95

Publications

3 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: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_001101426.4. Strenght limited to Supporting due to length of the change: 1aa.
PP5
Variant 7-16406315-CAAT-C is Pathogenic according to our data. Variant chr7-16406315-CAAT-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 31564.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CRPPANM_001101426.4 linkc.277_279delATT p.Ile93del conservative_inframe_deletion Exon 2 of 10 ENST00000407010.7 NP_001094896.1
CRPPANM_001368197.1 linkc.277_279delATT p.Ile93del conservative_inframe_deletion Exon 2 of 9 NP_001355126.1
CRPPANM_001101417.4 linkc.277_279delATT p.Ile93del conservative_inframe_deletion Exon 2 of 9 NP_001094887.1
CRPPANR_160656.1 linkn.493_495delATT non_coding_transcript_exon_variant Exon 2 of 8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CRPPAENST00000407010.7 linkc.277_279delATT p.Ile93del conservative_inframe_deletion Exon 2 of 10 5 NM_001101426.4 ENSP00000385478.2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152180
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000161
AC:
4
AN:
248722
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.0000646
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:
0.0000266
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461418
Hom.:
0
AF XY:
0.0000193
AC XY:
14
AN XY:
726990
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44698
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53382
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000270
AC:
30
AN:
1111664
Other (OTH)
AF:
0.00
AC:
0
AN:
60358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.428
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.0000460
AC:
7
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.0000673
AC XY:
5
AN XY:
74334
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41426
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68048
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.539
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

Genome 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
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000302

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1
Apr 27, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 07, 2022
Revvity Omics, Revvity
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Muscular dystrophy-dystroglycanopathy Pathogenic:1
Jun 15, 2016
Genetic Services Laboratory, University of Chicago
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7 Pathogenic:1
May 01, 2012
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7;C5190987:Autosomal recessive limb-girdle muscular dystrophy type 2U Pathogenic:1
Dec 12, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant, c.277_279del, results in the deletion of 1 amino acid(s) of the ISPD protein (p.Ile93del), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs397515398, gnomAD 0.008%). This variant has been observed in individual(s) with clinical features of Walker-Warburg syndrome (PMID: 2522420; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 31564). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
8.9
Mutation Taster
=29/71
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs397515398; hg19: chr7-16445940; API