14-77320429-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_ModeratePP5_Moderate

The NM_013382.7(POMT2):​c.248+5G>C variant causes a splice donor 5th base, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000129 in 1,546,540 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

POMT2
NM_013382.7 splice_donor_5th_base, intron

Scores

2
Splicing: ADA: 0.9999
2

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 3.46
Variant links:
Genes affected
POMT2 (HGNC:19743): (protein O-mannosyltransferase 2) The protein encoded by this gene is an O-mannosyltransferase that requires interaction with the product of the POMT1 gene for enzymatic function. The encoded protein is found in the membrane of the endoplasmic reticulum. Defects in this gene are a cause of Walker-Warburg syndrome (WWS).[provided by RefSeq, Oct 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 14-77320429-C-G is Pathogenic according to our data. Variant chr14-77320429-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3234.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr14-77320429-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
POMT2NM_013382.7 linkuse as main transcriptc.248+5G>C splice_donor_5th_base_variant, intron_variant ENST00000261534.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
POMT2ENST00000261534.9 linkuse as main transcriptc.248+5G>C splice_donor_5th_base_variant, intron_variant 1 NM_013382.7 P1Q9UKY4-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152240
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000680
AC:
1
AN:
146960
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
78572
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000180
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000122
AC:
17
AN:
1394300
Hom.:
0
Cov.:
30
AF XY:
0.0000116
AC XY:
8
AN XY:
687994
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000148
Gnomad4 OTH exome
AF:
0.0000173
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152240
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74374
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000567
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A2;C3150416:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B2;C3150418:Autosomal recessive limb-girdle muscular dystrophy type 2N Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingInvitaeSep 27, 2023This sequence change falls in intron 1 of the POMT2 gene. It does not directly change the encoded amino acid sequence of the POMT2 protein. RNA analysis indicates that this variant induces altered splicing and may result in an absent or disrupted protein product. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has been observed in individual(s) with congenital muscular dystrophy (PMID: 19138766). ClinVar contains an entry for this variant (Variation ID: 3234). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant results in activation of a cryptic splice site and introduces a premature termination codon (PMID: 19138766). The resulting mRNA is expected to undergo nonsense-mediated decay. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B2 Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMJul 01, 2009- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.26
CADD
Benign
21
DANN
Benign
0.92

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.98
SpliceAI score (max)
0.78
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.78
Position offset: 5

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: rs587777816; hg19: chr14-77786772; API