19-12646664-G-A

Position:

chr19-12646664-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5

The NM_000528.4(MAN2B1):c.2992C>T(p.Arg998Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000248 in 1,613,952 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R998H) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

MAN2B1
NM_000528.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 7.87

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 Likely_pathogenic. Variant got 9 ACMG points.

PM1

In a chain Lysosomal alpha-mannosidase E peptide (size 128) in uniprot entity MA2B1_HUMAN there are 7 pathogenic changes around while only 1 benign (88%) in NM_000528.4

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.969

PP5

Variant 19-12646664-G-A is Pathogenic according to our data. Variant chr19-12646664-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 2146799.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
MAN2B1	NM_000528.4 linkuse as main transcript	c.2992C>T	p.Arg998Cys	missense_variant	24/24	ENST00000456935.7	NP_000519.2
MAN2B1	NM_001173498.2 linkuse as main transcript	c.2989C>T	p.Arg997Cys	missense_variant	24/24		NP_001166969.1
MAN2B1	XM_005259913.3 linkuse as main transcript	c.2995C>T	p.Arg999Cys	missense_variant	24/24		XP_005259970.1
MAN2B1	XM_047438841.1 linkuse as main transcript	c.1891C>T	p.Arg631Cys	missense_variant	17/17		XP_047294797.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MAN2B1	ENST00000456935.7 linkuse as main transcript	c.2992C>T	p.Arg998Cys	missense_variant	24/24	1	NM_000528.4	ENSP00000395473	A1	O00754-1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152096

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.0000942

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000398

AC:

AN:

251482

Hom.:

AF XY:

0.0000441

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000462

Gnomad NFE exome

AF:

0.0000527

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000239

AC:

AN:

1461856

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727234

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000894

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.000150

Gnomad4 NFE exome

AF:

0.0000171

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152096

Hom.:

Cov.:

AF XY:

0.0000673

AC XY:

AN XY:

74286

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000942

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.0000302

ExAC

AF:

0.0000330

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Deficiency of alpha-mannosidase

Pathogenic:1Uncertain:1

Likely pathogenic, criteria provided, single submitter	research	Laboratory of Prof. Karen Avraham, Tel Aviv University	May 29, 2024	Homozygosity of a rare variant that is predicted to cause damage by most prediction programs -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 16, 2022	This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 998 of the MAN2B1 protein (p.Arg998Cys). This variant is present in population databases (rs758755293, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with MAN2B1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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

AlphaMissense

Benign

0.23

BayesDel_addAF

Pathogenic

0.27

BayesDel_noAF

Pathogenic

0.33

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.85

D;.

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.96

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

D;D

M_CAP

Benign

0.078

MetaRNN

Pathogenic

0.97

D;D

MetaSVM

Pathogenic

0.92

MutationAssessor

Pathogenic

3.9

H;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.60

PROVEAN

Pathogenic

-6.7

D;D

REVEL

Pathogenic

0.80

Sift

Pathogenic

0.0

D;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

D;.

Vest4

0.86

MutPred

0.88

Gain of sheet (P = 0.1539);.;

MVP

0.99

MPC

1.0

ClinPred

1.0

GERP RS

5.9

Varity_R

0.65

gMVP

0.89

Splicing

Name

Calibrated prediction

Score

Prediction

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