7-16308599-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM5

The NM_001101426.4(CRPPA):​c.713C>G​(p.Thr238Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,609,408 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T238A) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000012 ( 1 hom. )

Consequence

CRPPA
NM_001101426.4 missense

Scores

4
12
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 8.10
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 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 chr7-16308600-T-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CRPPANM_001101426.4 linkc.713C>G p.Thr238Ser missense_variant Exon 4 of 10 ENST00000407010.7 NP_001094896.1 A4D126-1
CRPPANM_001101417.4 linkc.563C>G p.Thr188Ser missense_variant Exon 3 of 9 NP_001094887.1 A4D126-2A0A140VJM1
CRPPANM_001368197.1 linkc.685-7133C>G intron_variant Intron 3 of 8 NP_001355126.1
CRPPANR_160656.1 linkn.901-30373C>G intron_variant Intron 3 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CRPPAENST00000407010.7 linkc.713C>G p.Thr238Ser missense_variant Exon 4 of 10 5 NM_001101426.4 ENSP00000385478.2 A4D126-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152140
Hom.:
0
Cov.:
33
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:
0.000414
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000368
AC:
9
AN:
244596
Hom.:
0
AF XY:
0.0000529
AC XY:
7
AN XY:
132368
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 SAS exome
AF:
0.000271
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000902
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000117
AC:
17
AN:
1457268
Hom.:
1
Cov.:
29
AF XY:
0.0000138
AC XY:
10
AN XY:
724654
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000141
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.02e-7
Gnomad4 OTH exome
AF:
0.0000332
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152140
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74308
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000414
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000425
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2U Uncertain:1
Aug 29, 2022
MGZ Medical Genetics Center
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7;C5190987:Autosomal recessive limb-girdle muscular dystrophy type 2U Uncertain:1
Feb 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with serine, which is neutral and polar, at codon 238 of the ISPD protein (p.Thr238Ser). This variant is present in population databases (rs397515409, gnomAD 0.02%). This missense change has been observed in individual(s) with clinical features of ISPD-related conditions (Invitae). ClinVar contains an entry for this variant (Variation ID: 1680772). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt ISPD protein function with a negative predictive value of 80%. This variant disrupts the p.Thr238 amino acid residue in ISPD. Other variant(s) that disrupt this residue have been observed in individuals with ISPD-related conditions (PMID: 23217329, 31909476), which suggests that this may be a clinically significant amino acid residue. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.49
BayesDel_addAF
Benign
-0.056
T
BayesDel_noAF
Uncertain
-0.020
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.67
D;.
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.81
T;T
M_CAP
Uncertain
0.11
D
MetaRNN
Uncertain
0.74
D;D
MetaSVM
Uncertain
0.35
D
MutationAssessor
Pathogenic
3.5
H;.
PrimateAI
Uncertain
0.52
T
PROVEAN
Uncertain
-3.9
D;D
REVEL
Uncertain
0.60
Sift
Uncertain
0.0040
D;T
Sift4G
Uncertain
0.033
D;D
Polyphen
1.0
D;.
Vest4
0.85
MutPred
0.49
Gain of helix (P = 0.1736);.;
MVP
0.76
MPC
0.34
ClinPred
0.95
D
GERP RS
5.3
Varity_R
0.87
gMVP
0.67

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs397515409; hg19: chr7-16348224; API