rs754733253

Positions:

Variant summary

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

The NM_000528.4(MAN2B1):c.2782G>C(p.Gly928Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000731 in 1,614,110 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in same amino acid change has been previously reported as Likely benignin ClinVar. Synonymous variant affecting the same amino acid position (i.e. G928G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000075 ( 1 hom. )

Consequence

MAN2B1
NM_000528.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:6

Conservation

PhyloP100: 0.709

Variant links:

Genes affected

MAN2B1 (HGNC:6826): (mannosidase alpha class 2B member 1) This gene encodes an enzyme that hydrolyzes terminal, non-reducing alpha-D-mannose residues in alpha-D-mannosides. Its activity is necessary for the catabolism of N-linked carbohydrates released during glycoprotein turnover and it is member of family 38 of glycosyl hydrolases. The full length protein is processed in two steps. First, a 49 aa leader sequence is cleaved off and the remainder of the protein is processed into 3 peptides of 70 kDa, 42 kDa (D) and 13/15 kDa (E). Next, the 70 kDa peptide is further processed into three peptides (A, B and C). The A, B and C peptides are disulfide-linked. Defects in this gene have been associated with lysosomal alpha-mannosidosis. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Mar 2010]

MAN2B1 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 (MetaRNN=0.016765296).

BP6

Variant 19-12647481-C-G is Benign according to our data. Variant chr19-12647481-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 287586.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Uncertain_significance=1}.

BS1

Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.0000752 (110/1461890) while in subpopulation AMR AF= 0.00246 (110/44724). AF 95% confidence interval is 0.00209. There are 1 homozygotes in gnomad4_exome. There are 42 alleles in male gnomad4_exome subpopulation. Median coverage is 33. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
MAN2B1	NM_000528.4 linkuse as main transcript	c.2782G>C	p.Gly928Arg	missense_variant	22/24	ENST00000456935.7
MAN2B1	NM_001173498.2 linkuse as main transcript	c.2779G>C	p.Gly927Arg	missense_variant	22/24
MAN2B1	XM_005259913.3 linkuse as main transcript	c.2785G>C	p.Gly929Arg	missense_variant	22/24
MAN2B1	XM_047438841.1 linkuse as main transcript	c.1681G>C	p.Gly561Arg	missense_variant	15/17

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MAN2B1	ENST00000456935.7 linkuse as main transcript	c.2782G>C	p.Gly928Arg	missense_variant	22/24	1	NM_000528.4	A1	O00754-1

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152220

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000523

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:

0.000362

AC:

AN:

251214

Hom.:

AF XY:

0.000258

AC XY:

AN XY:

135780

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00263

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

AF:

0.0000752

AC:

110

AN:

1461890

Hom.:

Cov.:

AF XY:

0.0000578

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00246

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:

0.00

GnomAD4 genome

AF:

0.0000526

AC:

AN:

152220

Hom.:

Cov.:

AF XY:

0.0000672

AC XY:

AN XY:

74356

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000523

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

Bravo

AF:

0.000136

ExAC

AF:

0.000296

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2Benign:6

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Deficiency of alpha-mannosidase

Uncertain:2Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 25, 2024	- -
Uncertain significance, no assertion criteria provided	clinical testing	Baylor Genetics	Oct 03, 2014	Our laboratory reported dual molecular diagnoses in SCN8A (NM_014191.3, c.647T>G) and MAN2B1 (NM_000528.3, c.2782G>C and c.1383C>G in trans) in one individual with reported features that include delayed motor milestones, delayed speech, intellectual disability, hypotonia, seizure disorder (refractory epilepsy), abnormal movements (dyskinesia), minor dysmorphic features (flat nasal bridge, prominent eyes, full lips), microcephaly, dysphagia, and cortical visual impairment. Heterozygotes for the MAN2B1 variants would be expected to be asymptomatic carriers. -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Sep 28, 2017	- -
Likely benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Sep 05, 2021	- -
Benign, no assertion criteria provided	clinical testing	Natera, Inc.	Jan 28, 2020	- -

not specified

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 22, 2022	Variant summary: MAN2B1 c.2782G>C (p.Gly928Arg) results in a non-conservative amino acid change located in the glycosyl hydrolases family 38, C-terminal beta sandwich domain (IPR041147) of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00036 in 251214 control chromosomes (gnomAD), predominantly at a frequency of 0.0026 within the Latino subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within Latino control individuals in the gnomAD database is approximately 1.64 fold of the estimated maximal expected allele frequency for a pathogenic variant in MAN2B1 causing Alpha-Mannosidosis (0.0016), suggesting that the variant is a benign polymorphism found primarily in populations of Latino origin. To our knowledge, no occurrence of c.2782G>C in individuals affected with Alpha-Mannosidosis and no experimental evidence demonstrating its impact on protein function have been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Three laboratories classified the variant as likely benign, one as benign, and one as VUS. Based on the evidence outlined above, the variant was classified as likely benign. -
Likely benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Apr 18, 2016	- -

MAN2B1-related disorder

Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Sep 25, 2024

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). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.085

BayesDel_addAF

Benign

-0.42

BayesDel_noAF

Benign

-0.38

CADD

Benign

DANN

Benign

0.77

DEOGEN2

Benign

0.30

T;.

Eigen

Benign

-0.90

Eigen_PC

Benign

-1.1

FATHMM_MKL

Benign

0.23

LIST_S2

Benign

0.48

T;T

M_CAP

Benign

0.022

MetaRNN

Benign

0.017

T;T

MetaSVM

Benign

-0.66

MutationAssessor

Uncertain

2.4

M;.

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.32

PROVEAN

Benign

-1.3

N;N

REVEL

Uncertain

0.32

Sift

Benign

0.54

T;T

Sift4G

Benign

0.17

T;T

Polyphen

0.94

P;.

Vest4

0.31

MutPred

0.39

Gain of solvent accessibility (P = 0.019);.;

MVP

0.78

MPC

0.67

ClinPred

0.12

GERP RS

-5.6

Varity_R

0.027

gMVP

0.53

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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