11-102609058-A-C

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_004771.4(MMP20):​c.690T>G​(p.His230Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 151,932 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 Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00033 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

MMP20
NM_004771.4 missense

Scores

12
2
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.234

Publications

0 publications found
Variant links:
Genes affected
MMP20 (HGNC:7167): (matrix metallopeptidase 20) Proteins of the matrix metalloproteinase (MMP) family are involved in the breakdown of extracellular matrix in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes, such as arthritis and metastasis. Most MMP's are secreted as inactive proproteins which are activated when cleaved by extracellular proteinases. The protein encoded by this gene degrades amelogenin, the major protein component of dental enamel matrix, and thus thought to play a role in tooth enamel formation. A mutation in this gene, which alters the normal splice pattern and results in premature termination of the encoded protein, has been associated with amelogenesis imperfecta. This gene is part of a cluster of MMP genes located on chromosome 11q22.3. [provided by RefSeq, Aug 2011]
MMP20-AS1 (HGNC:56362): (MMP20 antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_004771.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.982

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMP20NM_004771.4 linkc.690T>G p.His230Gln missense_variant Exon 5 of 10 ENST00000260228.3 NP_004762.2 O60882

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMP20ENST00000260228.3 linkc.690T>G p.His230Gln missense_variant Exon 5 of 10 1 NM_004771.4 ENSP00000260228.2 O60882
MMP20-AS1ENST00000542119.2 linkn.233+1606A>C intron_variant Intron 1 of 3 3
MMP20-AS1ENST00000782665.1 linkn.233+1606A>C intron_variant Intron 1 of 5

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151932
Hom.:
0
Cov.:
32
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251436
AF XY:
0.00000736
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
0.000330
AC:
464
AN:
1405362
Hom.:
0
Cov.:
32
AF XY:
0.000278
AC XY:
195
AN XY:
701722
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.000402
AC:
13
AN:
32354
American (AMR)
AF:
0.0000448
AC:
2
AN:
44642
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25764
East Asian (EAS)
AF:
0.0000508
AC:
2
AN:
39372
South Asian (SAS)
AF:
0.000117
AC:
10
AN:
85116
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53346
Middle Eastern (MID)
AF:
0.000176
AC:
1
AN:
5674
European-Non Finnish (NFE)
AF:
0.000400
AC:
424
AN:
1060514
Other (OTH)
AF:
0.000188
AC:
11
AN:
58580
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.241
Heterozygous variant carriers
0
75
151
226
302
377
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
24
48
72
96
120
<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:
0.00000658
AC:
1
AN:
151932
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74238
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41432
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10534
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67908
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Amelogenesis imperfecta hypomaturation type 2A2 Uncertain:1
Feb 23, 2023
3billion
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). Missense changes are a common disease-causing mechanism. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.91; 3Cnet: 0.97). Therefore, this variant is classified as VUS according to the recommendation of ACMG/AMP guideline. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.51
CADD
Benign
17
DANN
Uncertain
0.99
DEOGEN2
Benign
0.38
T
Eigen
Benign
-0.0099
Eigen_PC
Benign
-0.31
FATHMM_MKL
Benign
0.37
N
LIST_S2
Pathogenic
0.98
D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.98
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.1
H
PhyloP100
-0.23
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-7.8
D
REVEL
Pathogenic
0.91
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.97
MutPred
0.90
Gain of sheet (P = 0.0101);
MVP
0.95
MPC
0.27
ClinPred
1.0
D
GERP RS
-4.7
Varity_R
0.98
gMVP
0.89
Mutation Taster
=41/59
disease causing

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: rs781377746; hg19: chr11-102479789; API