chr16-87891785-CGGGCACGGCTCACCTGGCTTG-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PVS1_StrongPP5

The NM_001739.2(CA5A):​c.767_774+13del variant causes a splice donor, splice donor 5th base, coding sequence, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000131 in 152,232 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 0.00013 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000016 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

CA5A
NM_001739.2 splice_donor, splice_donor_5th_base, coding_sequence, intron

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 2.52
Variant links:
Genes affected
CA5A (HGNC:1377): (carbonic anhydrase 5A) Carbonic anhydrases (CAs) are a large family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide. They participate in a variety of biological processes, including respiration, calcification, acid-base balance, bone resorption, and the formation of aqueous humor, cerebrospinal fluid, saliva, and gastric acid. They show extensive diversity in tissue distribution and in their subcellular localization. CA VA is localized in the mitochondria and expressed primarily in the liver. It may play an important role in ureagenesis and gluconeogenesis. CA5A gene maps to chromosome 16q24.3 and an unprocessed pseudogene has been assigned to 16p12-p11.2. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.16884531 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PP5
Variant 16-87891785-CGGGCACGGCTCACCTGGCTTG-C is Pathogenic according to our data. Variant chr16-87891785-CGGGCACGGCTCACCTGGCTTG-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 962096.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CA5ANM_001739.2 linkuse as main transcriptc.767_774+13del splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant 6/7 ENST00000649794.3 NP_001730.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CA5AENST00000649794.3 linkuse as main transcriptc.767_774+13del splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant 6/7 NM_001739.2 ENSP00000498065 P1

Frequencies

GnomAD3 genomes
AF:
0.000131
AC:
20
AN:
152232
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.000458
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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
GnomAD3 exomes
AF:
0.0000339
AC:
5
AN:
147516
Hom.:
0
AF XY:
0.0000244
AC XY:
2
AN XY:
81944
show subpopulations
Gnomad AFR exome
AF:
0.000542
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
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
Data not reliable, filtered out with message: AS_VQSR
AF:
0.0000158
AC:
21
AN:
1332498
Hom.:
0
AF XY:
0.0000168
AC XY:
11
AN XY:
653852
show subpopulations
Gnomad4 AFR exome
AF:
0.000747
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.0000183
GnomAD4 genome
AF:
0.000131
AC:
20
AN:
152232
Hom.:
0
Cov.:
31
AF XY:
0.000148
AC XY:
11
AN XY:
74358
show subpopulations
Gnomad4 AFR
AF:
0.000458
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000214
Hom.:
0
Bravo
AF:
0.000181

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxNov 10, 2023Has not been previously published as pathogenic or benign to our knowledge; Canonical splice site variant expected to result in aberrant splicing, although in the absence of functional evidence the actual effect of this sequence change is unknown -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpApr 14, 2023Variant summary: CA5A c.767_774+13del21 is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a frameshift downstream of the expected nonsense mediated decay region. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes the canonical 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 3.4e-05 in 147516 control chromosomes (gnomAD). To our knowledge, no occurrence of c.767_774+13del21 in individuals affected with Hyperammonemic Encephalopathy Due To Carbonic Anhydrase VA Deficiency and no experimental evidence demonstrating its impact on protein function have been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as likely pathogenic, and as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Hyperammonemic encephalopathy due to carbonic anhydrase VA deficiency Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 07, 2023This variant is present in population databases (rs762768981, gnomAD 0.05%). This variant results in the deletion of part of exon 6 (c.767_774+13del) of the CA5A gene. While this variant is not anticipated to result in nonsense mediated decay, it likely alters RNA splicing and results in a disrupted protein product. This variant has been observed in individual(s) with clinical features of CA5A related conditions (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 962096). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). 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

Splicing

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: rs762768981; hg19: chr16-87925391; API