12-9068842-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_000014.6(A2M):​c.4264G>A​(p.Val1422Met) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000441 in 1,585,712 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000042 ( 0 hom. )

Consequence

A2M
NM_000014.6 missense, splice_region

Scores

9
10
Splicing: ADA: 0.4512
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.864
Variant links:
Genes affected
A2M (HGNC:7): (alpha-2-macroglobulin) The protein encoded by this gene is a protease inhibitor and cytokine transporter. It uses a bait-and-trap mechanism to inhibit a broad spectrum of proteases, including trypsin, thrombin and collagenase. It can also inhibit inflammatory cytokines, and it thus disrupts inflammatory cascades. Mutations in this gene are a cause of alpha-2-macroglobulin deficiency. This gene is implicated in Alzheimer's disease (AD) due to its ability to mediate the clearance and degradation of A-beta, the major component of beta-amyloid deposits. A related pseudogene, which is also located on the p arm of chromosome 12, has been identified. [provided by RefSeq, Nov 2016]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2
High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
A2MNM_000014.6 linkuse as main transcriptc.4264G>A p.Val1422Met missense_variant, splice_region_variant 34/36 ENST00000318602.12

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
A2MENST00000318602.12 linkuse as main transcriptc.4264G>A p.Val1422Met missense_variant, splice_region_variant 34/361 NM_000014.6 P1
A2MENST00000495442.1 linkuse as main transcriptn.114G>A non_coding_transcript_exon_variant 1/23
A2MENST00000495709.1 linkuse as main transcriptn.237G>A non_coding_transcript_exon_variant 1/32
A2MENST00000543436.2 linkuse as main transcriptn.452-1030G>A intron_variant, non_coding_transcript_variant 5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152138
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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
GnomAD4 exome
AF:
0.00000419
AC:
6
AN:
1433574
Hom.:
0
Cov.:
29
AF XY:
0.00000282
AC XY:
2
AN XY:
709816
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000127
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.11e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152138
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74320
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756
ExAC
AF:
0.00000829
AC:
1

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsDec 06, 2021The c.4264G>A (p.V1422M) alteration is located in exon 34 (coding exon 34) of the A2M gene. This alteration results from a G to A substitution at nucleotide position 4264, causing the valine (V) at amino acid position 1422 to be replaced by a methionine (M). 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
Benign
0.27
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.45
CADD
Uncertain
23
DANN
Uncertain
0.99
DEOGEN2
Benign
0.093
T
Eigen
Uncertain
0.22
Eigen_PC
Uncertain
0.26
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.83
T
M_CAP
Benign
0.0042
T
MetaRNN
Uncertain
0.48
T
MetaSVM
Benign
-0.86
T
MutationAssessor
Uncertain
2.3
M
MutationTaster
Benign
0.67
D
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
-1.6
N
REVEL
Benign
0.14
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.0080
D
Polyphen
0.57
P
Vest4
0.31
MutPred
0.85
Loss of methylation at K1421 (P = 0.0273);
MVP
0.62
MPC
0.24
ClinPred
0.85
D
GERP RS
3.6
Varity_R
0.36
gMVP
0.16

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.45
dbscSNV1_RF
Benign
0.50
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.

Other links and lift over

dbSNP: rs754217279; hg19: chr12-9221438; API