16-25132414-G-A

Variant summary

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

The NM_016309.3(LCMT1):​c.218G>A​(p.Arg73Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,482 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: not found (cov: 31)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

LCMT1
NM_016309.3 missense

Scores

10
8
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.30

Publications

1 publications found
Variant links:
Genes affected
LCMT1 (HGNC:17557): (leucine carboxyl methyltransferase 1) LCMT1 catalyzes the methylation of the carboxyl group of the C-terminal leucine residue (leu309) of the catalytic subunit of protein phosphatase-2A (PPP2CA; MIM 176915) (De Baere et al., 1999 [PubMed 10600115]).[supplied by OMIM, Mar 2008]

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 binding_site (size 0) in uniprot entity LCMT1_HUMAN
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LCMT1NM_016309.3 linkc.218G>A p.Arg73Gln missense_variant Exon 3 of 11 ENST00000399069.8 NP_057393.2 Q9UIC8-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LCMT1ENST00000399069.8 linkc.218G>A p.Arg73Gln missense_variant Exon 3 of 11 1 NM_016309.3 ENSP00000382021.3 Q9UIC8-1
LCMT1ENST00000380962.9 linkn.*75G>A non_coding_transcript_exon_variant Exon 4 of 12 2 ENSP00000370349.5 H7BYF0
LCMT1ENST00000380962.9 linkn.*75G>A 3_prime_UTR_variant Exon 4 of 12 2 ENSP00000370349.5 H7BYF0

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461482
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
727044
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44708
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53314
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111780
Other (OTH)
AF:
0.00
AC:
0
AN:
60372
⚠️ 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: 0.375
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

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
Cov.:
31

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Jan 23, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.218G>A (p.R73Q) alteration is located in exon 3 (coding exon 3) of the LCMT1 gene. This alteration results from a G to A substitution at nucleotide position 218, causing the arginine (R) at amino acid position 73 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.26
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.48
T;.;.
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Pathogenic
0.99
D;D;D
M_CAP
Uncertain
0.15
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Uncertain
0.016
D
MutationAssessor
Pathogenic
4.0
H;H;.
PhyloP100
9.3
PrimateAI
Uncertain
0.54
T
PROVEAN
Uncertain
-3.9
D;D;.
REVEL
Uncertain
0.50
Sift
Pathogenic
0.0
D;D;.
Sift4G
Uncertain
0.0040
D;D;D
Polyphen
1.0
D;D;.
Vest4
0.97
MutPred
0.96
Loss of methylation at R73 (P = 0.0244);Loss of methylation at R73 (P = 0.0244);.;
MVP
0.79
MPC
0.96
ClinPred
1.0
D
GERP RS
3.5
Varity_R
0.91
gMVP
0.93
Mutation Taster
=33/67
disease causing

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

Other links and lift over

dbSNP: rs995675568; hg19: chr16-25143735; COSMIC: COSV66725785; API