19-12663723-G-A

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_000528.4(MAN2B1):​c.743C>T​(p.Pro248Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00434 in 1,612,812 control chromosomes in the GnomAD database, including 28 homozygotes. In-silico tool predicts a benign 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. P248R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0023 ( 1 hom., cov: 32)
Exomes 𝑓: 0.0046 ( 27 hom. )

Consequence

MAN2B1
NM_000528.4 missense

Scores

5
11
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:8

Conservation

PhyloP100: 7.35
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]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.03565052).
BP6
Variant 19-12663723-G-A is Benign according to our data. Variant chr19-12663723-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 197684.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=2, Likely_benign=4}. Variant chr19-12663723-G-A is described in Lovd as [Likely_benign].
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00234 (356/152292) while in subpopulation NFE AF = 0.00406 (276/67998). AF 95% confidence interval is 0.00367. There are 1 homozygotes in GnomAd4. There are 161 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position FAILED quality control check.
BS2
High Homozygotes in GnomAdExome4 at 27 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MAN2B1NM_000528.4 linkc.743C>T p.Pro248Leu missense_variant Exon 5 of 24 ENST00000456935.7 NP_000519.2 O00754-1
MAN2B1NM_001173498.2 linkc.743C>T p.Pro248Leu missense_variant Exon 5 of 24 NP_001166969.1 O00754-2A8K6A7
MAN2B1XM_005259913.3 linkc.743C>T p.Pro248Leu missense_variant Exon 5 of 24 XP_005259970.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MAN2B1ENST00000456935.7 linkc.743C>T p.Pro248Leu missense_variant Exon 5 of 24 1 NM_000528.4 ENSP00000395473.2 O00754-1
MAN2B1ENST00000221363.8 linkc.743C>T p.Pro248Leu missense_variant Exon 5 of 24 1 ENSP00000221363.4 O00754-2
MAN2B1ENST00000486847.2 linkc.446C>T p.Pro149Leu missense_variant Exon 3 of 4 4 ENSP00000470174.1 M0QYZ1
MAN2B1ENST00000466794.5 linkn.725C>T non_coding_transcript_exon_variant Exon 5 of 22 2

Frequencies

GnomAD3 genomes
AF:
0.00234
AC:
356
AN:
152174
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000796
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00144
Gnomad ASJ
AF:
0.00115
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00145
Gnomad FIN
AF:
0.00104
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00406
Gnomad OTH
AF:
0.00143
GnomAD2 exomes
AF:
0.00230
AC:
570
AN:
247534
AF XY:
0.00241
show subpopulations
Gnomad AFR exome
AF:
0.000693
Gnomad AMR exome
AF:
0.00152
Gnomad ASJ exome
AF:
0.000300
Gnomad EAS exome
AF:
0.0000549
Gnomad FIN exome
AF:
0.00138
Gnomad NFE exome
AF:
0.00355
Gnomad OTH exome
AF:
0.00330
GnomAD4 exome
AF:
0.00455
AC:
6646
AN:
1460520
Hom.:
27
Cov.:
32
AF XY:
0.00444
AC XY:
3224
AN XY:
726580
show subpopulations
Gnomad4 AFR exome
AF:
0.000687
AC:
23
AN:
33456
Gnomad4 AMR exome
AF:
0.00132
AC:
59
AN:
44530
Gnomad4 ASJ exome
AF:
0.000460
AC:
12
AN:
26106
Gnomad4 EAS exome
AF:
0.00
AC:
0
AN:
39680
Gnomad4 SAS exome
AF:
0.00186
AC:
160
AN:
86168
Gnomad4 FIN exome
AF:
0.00117
AC:
62
AN:
53008
Gnomad4 NFE exome
AF:
0.00548
AC:
6094
AN:
1111590
Gnomad4 Remaining exome
AF:
0.00380
AC:
229
AN:
60332
Heterozygous variant carriers
0
389
778
1168
1557
1946
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Exome Het
Exome Hom
Variant carriers
0
250
500
750
1000
1250
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00234
AC:
356
AN:
152292
Hom.:
1
Cov.:
32
AF XY:
0.00216
AC XY:
161
AN XY:
74472
show subpopulations
Gnomad4 AFR
AF:
0.000794
AC:
0.000793956
AN:
0.000793956
Gnomad4 AMR
AF:
0.00144
AC:
0.00143791
AN:
0.00143791
Gnomad4 ASJ
AF:
0.00115
AC:
0.0011534
AN:
0.0011534
Gnomad4 EAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 SAS
AF:
0.00145
AC:
0.00144928
AN:
0.00144928
Gnomad4 FIN
AF:
0.00104
AC:
0.00103559
AN:
0.00103559
Gnomad4 NFE
AF:
0.00406
AC:
0.00405894
AN:
0.00405894
Gnomad4 OTH
AF:
0.00142
AC:
0.00141777
AN:
0.00141777
Heterozygous variant carriers
0
18
37
55
74
92
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Genome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00317
Hom.:
7
Bravo
AF:
0.00257
ESP6500AA
AF:
0.000908
AC:
4
ESP6500EA
AF:
0.00419
AC:
36
ExAC
AF:
0.00235
AC:
285
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:8
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Deficiency of alpha-mannosidase Uncertain:2Benign:3
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Dec 27, 2019
Natera, Inc.
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 05, 2021
Genome-Nilou Lab
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 21, 2017
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:3
Jul 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

MAN2B1: BS2 -

-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not specified Benign:1
Mar 30, 2015
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

MAN2B1-related disorder Benign:1
Mar 12, 2021
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

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
0.19
BayesDel_addAF
Uncertain
0.048
T
BayesDel_noAF
Pathogenic
0.29
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.64
D;.;.
Eigen
Pathogenic
0.72
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.96
D;D;D
M_CAP
Uncertain
0.19
D
MetaRNN
Benign
0.036
T;T;T
MetaSVM
Uncertain
0.41
D
MutationAssessor
Uncertain
2.5
M;M;.
PrimateAI
Uncertain
0.51
T
PROVEAN
Pathogenic
-6.1
D;D;.
REVEL
Pathogenic
0.68
Sift
Uncertain
0.010
D;D;.
Sift4G
Uncertain
0.013
D;D;.
Polyphen
1.0
D;.;.
Vest4
0.45
MVP
0.94
MPC
1.5
ClinPred
0.023
T
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.37
gMVP
0.72
Mutation Taster
=95/5
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.060
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.

Other links and lift over

dbSNP: rs117843968; hg19: chr19-12774537; COSMIC: COSV55475040; COSMIC: COSV55475040; API