NM_016219.5:c.1189G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2PP3_StrongPP5

The NM_016219.5(MAN1B1):​c.1189G>A​(p.Glu397Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,613,698 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).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

MAN1B1
NM_016219.5 missense

Scores

11
7
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 7.62

Publications

10 publications found
Variant links:
Genes affected
MAN1B1 (HGNC:6823): (mannosidase alpha class 1B member 1) This gene encodes an enzyme belonging to the glycosyl hydrolase 47 family. This enzyme functions in N-glycan biosynthesis, and is a class I alpha-1,2-mannosidase that specifically converts Man9GlcNAc to Man8GlcNAc isomer B. It is required for N-glycan trimming to Man5-6GlcNAc2 in the endoplasmic-reticulum-associated degradation pathway. Mutations in this gene cause autosomal-recessive intellectual disability. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 11. [provided by RefSeq, Dec 2011]
MAN1B1 Gene-Disease associations (from GenCC):
  • MAN1B1-congenital disorder of glycosylation
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • Rafiq syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • autosomal recessive non-syndromic intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.944
PP5
Variant 9-137101607-G-A is Pathogenic according to our data. Variant chr9-137101607-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 30413.We mark this variant Likely_pathogenic, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MAN1B1NM_016219.5 linkc.1189G>A p.Glu397Lys missense_variant Exon 8 of 13 ENST00000371589.9 NP_057303.2 Q9UKM7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MAN1B1ENST00000371589.9 linkc.1189G>A p.Glu397Lys missense_variant Exon 8 of 13 1 NM_016219.5 ENSP00000360645.4 Q9UKM7

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152240
Hom.:
0
Cov.:
33
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251080
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000116
AC:
17
AN:
1461458
Hom.:
0
Cov.:
33
AF XY:
0.0000124
AC XY:
9
AN XY:
727004
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000189
AC:
1
AN:
53036
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1111976
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000131
AC:
2
AN:
152240
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000212
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Jan 26, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate a damaging effect (reduction of enzyme activity to below detectable levels) (Rafiq et al., 2011); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26279649, 23865144, 21763484, 28397838, 24176302, 34831340, 34258140, 26205822) -

Sep 01, 2016
CeGaT Center for Human Genetics Tuebingen
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Rafiq syndrome Pathogenic:1Uncertain:1
Feb 25, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. 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"). ClinVar contains an entry for this variant (Variation ID: 30413). This missense change has been observed in individual(s) with clinical features of MAN1B1-congenital disorder of glycosylation (PMID: 21763484). This variant is present in population databases (rs387906885, gnomAD 0.004%). This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 397 of the MAN1B1 protein (p.Glu397Lys). -

Jul 15, 2011
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Inborn genetic diseases Pathogenic:1
Oct 21, 2024
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1189G>A (p.E397K) alteration is located in exon 8 (coding exon 8) of the MAN1B1 gene. This alteration results from a G to A substitution at nucleotide position 1189, causing the glutamic acid (E) at amino acid position 397 to be replaced by a lysine (K). Based on data from gnomAD, the A allele has an overall frequency of 0.001% (2/282494) total alleles studied. The highest observed frequency was 0.004% (1/25112) of European (Finnish) alleles. This variant has been identified in the homozygous state and/or in conjunction with other MAN1B1 variants in individuals with features consistent with MAN1B1-related congenital disorder of glycosylation type II (Rafiq, 2011; external communication, 2024). This amino acid position is highly conserved in available vertebrate species. Functional studies suggest this variant causes a loss-of-function effect; however, additional evidence is needed to confirm this finding (Rafiq, 2011). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.35
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.77
D;D
Eigen
Pathogenic
0.69
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.89
D;D
M_CAP
Pathogenic
0.32
D
MetaRNN
Pathogenic
0.94
D;D
MetaSVM
Pathogenic
0.80
D
MutationAssessor
Pathogenic
4.2
H;.
PhyloP100
7.6
PrimateAI
Uncertain
0.73
T
PROVEAN
Uncertain
-3.5
D;.
REVEL
Pathogenic
0.85
Sift
Uncertain
0.0010
D;.
Sift4G
Uncertain
0.0030
D;D
Polyphen
1.0
D;.
Vest4
0.85
MutPred
0.79
Gain of ubiquitination at E397 (P = 0.0155);.;
MVP
0.86
MPC
0.43
ClinPred
1.0
D
GERP RS
4.6
Varity_R
0.99
gMVP
0.94
Mutation Taster
=2/98
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs387906885; hg19: chr9-139996059; COSMIC: COSV65377962; COSMIC: COSV65377962; API