NM_144670.6:c.1476+8C>G

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_144670.6(A2ML1):​c.1476+8C>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000413 in 1,611,082 control chromosomes in the GnomAD database, including 5 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.00045 ( 1 hom., cov: 32)
Exomes 𝑓: 0.00041 ( 4 hom. )

Consequence

A2ML1
NM_144670.6 splice_region, intron

Scores

2
Splicing: ADA: 0.0007122
2

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:2

Conservation

PhyloP100: -0.144

Publications

3 publications found
Variant links:
Genes affected
A2ML1 (HGNC:23336): (alpha-2-macroglobulin like 1) This gene encodes a member of the alpha-macroglobulin superfamily. The encoded protein is thought to be an N-glycosylated monomeric protein that acts as an inhibitor of several proteases. It has been shown to form covalent interactions with proteases, and has been reported as the p170 antigen recognized by autoantibodies in the autoimmune disease paraneoplastic pemphigus (PNP; PMID:20805888). Mutations in these gene have also been associated with some cases of Noonan syndrome (NS; PMID:24939586) as well as some cases of otitis media (PMID:26121085). Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Aug 2015]
A2ML1 Gene-Disease associations (from GenCC):
  • Noonan syndrome
    Inheritance: AD Classification: SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Genomics England PanelApp, ClinGen, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -16 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.85).
BP6
Variant 12-8843369-C-G is Benign according to our data. Variant chr12-8843369-C-G is described in ClinVar as Benign. ClinVar VariationId is 413816.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAd4 at 69 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
A2ML1NM_144670.6 linkc.1476+8C>G splice_region_variant, intron_variant Intron 12 of 35 ENST00000299698.12 NP_653271.3 B3KVV6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
A2ML1ENST00000299698.12 linkc.1476+8C>G splice_region_variant, intron_variant Intron 12 of 35 1 NM_144670.6 ENSP00000299698.7 A8K2U0-1
A2ML1ENST00000541459.5 linkc.126+8C>G splice_region_variant, intron_variant Intron 1 of 24 2 ENSP00000443174.1 H0YGG5

Frequencies

GnomAD3 genomes
AF:
0.000461
AC:
70
AN:
151984
Hom.:
1
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:
0.0114
Gnomad SAS
AF:
0.00125
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000768
AC:
191
AN:
248584
AF XY:
0.000689
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00991
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000444
Gnomad OTH exome
AF:
0.000331
GnomAD4 exome
AF:
0.000409
AC:
596
AN:
1458980
Hom.:
4
Cov.:
32
AF XY:
0.000415
AC XY:
301
AN XY:
725138
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33430
American (AMR)
AF:
0.0000224
AC:
1
AN:
44674
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.0124
AC:
493
AN:
39612
South Asian (SAS)
AF:
0.000255
AC:
22
AN:
86174
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53392
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.0000568
AC:
63
AN:
1109520
Other (OTH)
AF:
0.000282
AC:
17
AN:
60310
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.497
Heterozygous variant carriers
0
36
72
107
143
179
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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
GnomAD4 genome
AF:
0.000454
AC:
69
AN:
152102
Hom.:
1
Cov.:
32
AF XY:
0.000498
AC XY:
37
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41486
American (AMR)
AF:
0.00
AC:
0
AN:
15252
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.0114
AC:
59
AN:
5182
South Asian (SAS)
AF:
0.00104
AC:
5
AN:
4810
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68002
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
3
6
10
13
16
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:
0.00
Hom.:
13
Bravo
AF:
0.000529

ClinVar

Significance: Benign
Submissions summary: Benign:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:1
Feb 13, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: A2ML1 c.1476+8C>G alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00077 in 248584 control chromosomes, predominantly at a frequency of 0.0099 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 2475 fold of the estimated maximal expected allele frequency for a pathogenic variant in A2ML1 causing Noonan Syndrome phenotype (4e-06), strongly suggesting that the variant is a benign polymorphism found primarily in populations of East Asian origin. To our knowledge, no occurrence of c.1476+8C>G in individuals affected with Noonan Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. A ClinVar submitter (evaluation after 2014) cites the variant as benign. Based on the evidence outlined above, the variant was classified as benign. -

not provided Benign:1
Jan 16, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.85
CADD
Benign
0.47
DANN
Benign
0.40
PhyloP100
-0.14
PromoterAI
0.0079
Neutral
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00071
dbscSNV1_RF
Benign
0.010
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: rs75676135; hg19: chr12-8995965; API