chr7-16301440-C-T

Variant names:

• chr7-16301440-C-T
• rs754348253
• NM_001101426.4:c.816G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Moderate BP6_Moderate BP7

The NM_001101426.4(CRPPA):​c.816G>A​(p.Ala272Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000685 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: 𝑓 0.0 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CRPPA NM_001101426.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -1.19
• Publications: 0 publications found

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

ACMG classification

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=-0.31).
• BP6: Variant 7-16301440-C-T is Benign according to our data. Variant chr7-16301440-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 473158.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-1.19 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001101426.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRPPA	NM_001101426.4	MANE Select	c.816G>A	p.Ala272Ala	synonymous	Exon 5 of 10	NP_001094896.1	A4D126-1
	CRPPA	NM_001368197.1		c.711G>A	p.Ala237Ala	synonymous	Exon 4 of 9	NP_001355126.1
	CRPPA	NM_001101417.4		c.666G>A	p.Ala222Ala	synonymous	Exon 4 of 9	NP_001094887.1	A0A140VJM1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRPPA	ENST00000407010.7	TSL:5 MANE Select	c.816G>A	p.Ala272Ala	synonymous	Exon 5 of 10	ENSP00000385478.2	A4D126-1
	CRPPA	ENST00000399310.3	TSL:1	c.666G>A	p.Ala222Ala	synonymous	Exon 4 of 9	ENSP00000382249.3	A4D126-2
	CRPPA	ENST00000856526.1		c.816G>A	p.Ala272Ala	synonymous	Exon 5 of 8	ENSP00000526585.1

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 152050 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: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000121 AC: 3 AN: 248094 AF XY: 0.0000149

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000581

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000889

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000685 AC: 10 AN: 1460534 Hom.: 0 Cov.: 29 AF XY: 0.00000826 AC XY: 6 AN XY: 726488

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.0000448 AC: 2 AN: 44680

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 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: 0.00000630 AC: 7 AN: 1111220

Other (OTH) AF: 0.00 AC: 0 AN: 60326

GnomAD4 genome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 152050 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74252

African (AFR) AF: 0.00 AC: 0 AN: 41416

American (AMR) AF: 0.00 AC: 0 AN: 15250

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5174

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10586

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68012

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000468 Hom.: 0

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

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

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Benign	8.5
DANN	Benign	0.67
PhyloP100		-1.2

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs754348253; hg19: chr7-16341065;