rs189274856

chr1-46195931-G-T

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 2P and 9B. PM2BP4_StrongBP6BS1

The NM_017739.4(POMGNT1):c.421-7C>A variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000496 in 1,614,140 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00044 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00050 ( 1 hom. )

Consequence

POMGNT1
NM_017739.4 splice_region, splice_polypyrimidine_tract, intron

Scores

Splicing: ADA: 0.1135

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:5

Conservation

PhyloP100: 1.43

Variant links:

Genes affected

POMGNT1 (HGNC:19139): (protein O-linked mannose N-acetylglucosaminyltransferase 1 (beta 1,2-)) This gene encodes a type II transmembrane protein that resides in the Golgi apparatus. It participates in O-mannosyl glycosylation and is specific for alpha linked terminal mannose. Mutations in this gene may be associated with muscle-eye-brain disease and several congenital muscular dystrophies. Alternatively spliced transcript variants that encode different protein isoforms have been described. [provided by RefSeq, Feb 2014]

POMGNT1 links:

TSPAN1 (HGNC:):

TSPAN1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.78).

BP6

Variant 1-46195931-G-T is Benign according to our data. Variant chr1-46195931-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 198222.We mark this variant Likely_benign, oryginal submissions are: {Benign=1, Likely_benign=3, Uncertain_significance=5}.

BS1

Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.000502 (734/1461854) while in subpopulation AMR AF= 0.00221 (99/44722). AF 95% confidence interval is 0.00186. There are 1 homozygotes in gnomad4_exome. There are 342 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POMGNT1	NM_017739.4 linkuse as main transcript	c.421-7C>A		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000371984.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POMGNT1	ENST00000371984.8 linkuse as main transcript	c.421-7C>A		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_017739.4	P1	Q8WZA1-1

Frequencies

GnomAD3 genomes

AF:

0.000440

AC:

AN:

152168

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00164

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:

0.000470

Gnomad OTH

AF:

0.00239

GnomAD3 exomes

AF:

0.000525

AC:

132

AN:

251282

Hom.:

AF XY:

0.000449

AC XY:

AN XY:

135838

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00179

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:

0.000502

Gnomad OTH exome

AF:

0.00212

GnomAD4 exome

AF:

0.000502

AC:

734

AN:

1461854

Hom.:

Cov.:

AF XY:

0.000470

AC XY:

342

AN XY:

727226

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00221

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:

0.000538

Gnomad4 OTH exome

AF:

0.000613

GnomAD4 genome

AF:

0.000440

AC:

AN:

152286

Hom.:

Cov.:

AF XY:

0.000510

AC XY:

AN XY:

74456

show subpopulations

Gnomad4 AFR

AF:

0.000120

Gnomad4 AMR

AF:

0.00163

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000470

Gnomad4 OTH

AF:

0.00237

Alfa

AF:

0.000458

Hom.:

Bravo

AF:

0.000805

EpiCase

AF:

0.000327

EpiControl

AF:

0.000356

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5Benign:5

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Athena Diagnostics	Aug 25, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Feb 09, 2018	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2024	POMGNT1: BP4 -

not specified

Uncertain:1Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Mar 08, 2024	Variant summary: POMGNT1 c.421-7C>A alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00053 in 251282 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in POMGNT1 causing Limb-Girdle Muscular Dystrophy, Autosomal Recessive (0.00053 vs 0.00072), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.421-7C>A in individuals affected with Limb-Girdle Muscular Dystrophy, Autosomal Recessive and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 198222). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Sep 04, 2015	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. -

Autosomal recessive limb-girdle muscular dystrophy type 2O

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Congenital Muscular Dystrophy, alpha-dystroglycan related

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B3;C3150417:Autosomal recessive limb-girdle muscular dystrophy type 2O

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 31, 2024

- -

POMGNT1-related disorder

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 16, 2022

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Muscle eye brain disease

Benign:1

Likely benign, no assertion criteria provided

clinical testing

Natera, Inc.

Nov 11, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.78

Cadd

Benign

Dann

Benign

0.66

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.11

dbscSNV1_RF

Benign

0.22

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over