rs377582530

chr7-16278126-T-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP6

The NM_001101426.4(CRPPA):c.933+3A>G variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000226 in 1,462,138 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: CRPPA NM_001101426.4 splice_donor_region, intron
• Scores: Splicing: ADA: 0.008477
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 0.856

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]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.38).
• BP6: Variant 7-16278126-T-C is Benign according to our data. Variant chr7-16278126-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 387587.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=2, Likely_benign=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CRPPA	NM_001101426.4	c.933+3A>G		splice_donor_region_variant, intron_variant		ENST00000407010.7
CRPPA	NM_001101417.4	c.783+3A>G		splice_donor_region_variant, intron_variant
CRPPA	NM_001368197.1	c.828+3A>G		splice_donor_region_variant, intron_variant
CRPPA	NR_160656.1	n.998+3A>G		splice_donor_region_variant, intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CRPPA	ENST00000407010.7	c.933+3A>G		splice_donor_region_variant, intron_variant		5	NM_001101426.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152190 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: 0.000578

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000798 AC: 17 AN: 212954 Hom.: 0 AF XY: 0.0000784 AC XY: 9 AN XY: 114778

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00106

Gnomad SAS 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: 0.0000221 AC: 29 AN: 1309830 Hom.: 0 Cov.: 19 AF XY: 0.0000213 AC XY: 14 AN XY: 656220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000516

Gnomad4 SAS exome AF: 0.0000252

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.000127

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152308 Hom.: 0 Cov.: 32 AF XY: 0.0000268 AC XY: 2 AN XY: 74488

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000580

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000302

Asia WGS AF: 0.00260 AC: 9 AN: 3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not specified Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Aug 02, 2016	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	Athena Diagnostics	Dec 12, 2016	- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 7;C5190987:Autosomal recessive limb-girdle muscular dystrophy type 2U Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 12, 2023

This sequence change falls in intron 6 of the ISPD gene. It does not directly change the encoded amino acid sequence of the ISPD protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs377582530, gnomAD 0.1%). This variant has not been reported in the literature in individuals affected with ISPD-related conditions. ClinVar contains an entry for this variant (Variation ID: 387587). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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
BayesDel_noAF	Benign	-0.38
Cadd	Benign	19
Dann	Benign	0.91

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0085
dbscSNV1_RF	Benign	0.24
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

Other links and lift over

dbSNP: rs377582530; hg19: chr7-16317751;