rs200764174

Variant names:

• chr12-8822714-G-A
• rs200764174
• NM_144670.6:c.62+1G>A

Your query was ambiguous. Multiple possible variants found:

• chr12-8822714-G-A
• chr12-8822714-G-C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PVS1_Moderate BS2

The NM_144670.6(A2ML1):​c.62+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000279 in 1,613,962 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000053 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000025 (0 hom.)
• Consequence: A2ML1 NM_144670.6 splice_donor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.905
• Publications: 2 publications found

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-AS1 (HGNC:41022): (A2ML1 antisense RNA 1)

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.021305842 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• BS2: High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
A2ML1	NM_144670.6	c.62+1G>A		splice_donor_variant, intron_variant	Intron 1 of 35	ENST00000299698.12	NP_653271.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
A2ML1	ENST00000299698.12	c.62+1G>A		splice_donor_variant, intron_variant	Intron 1 of 35	1	NM_144670.6	ENSP00000299698.7
A2ML1-AS1	ENST00000537288.1	n.286+7948C>T		intron_variant	Intron 1 of 1	3

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152224 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000482

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: 0.0000882

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000281 AC: 7 AN: 249522 AF XY: 0.0000369

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.000199

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000353

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000253 AC: 37 AN: 1461738 Hom.: 0 Cov.: 30 AF XY: 0.0000275 AC XY: 20 AN XY: 727164

African (AFR) AF: 0.0000299 AC: 1 AN: 33476

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.000115 AC: 3 AN: 26134

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39700

South Asian (SAS) AF: 0.0000348 AC: 3 AN: 86242

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000216 AC: 24 AN: 1111890

Other (OTH) AF: 0.0000497 AC: 3 AN: 60386

GnomAD4 genome AF: 0.0000526 AC: 8 AN: 152224 Hom.: 0 Cov.: 32 AF XY: 0.0000538 AC XY: 4 AN XY: 74370

African (AFR) AF: 0.0000482 AC: 2 AN: 41458

American (AMR) AF: 0.00 AC: 0 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5202

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000882 AC: 6 AN: 68042

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000263 Hom.: 0

Bravo AF: 0.0000453

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000242 AC: 2

ExAC AF: 0.0000331 AC: 4

EpiCase AF: 0.000109

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Feb 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 1 of the A2ML1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), however the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in A2ML1 cause disease. This variant is present in population databases (rs200764174, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with A2ML1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2055109). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	0.030
CADD	Uncertain	24
DANN	Benign	0.95
Eigen	Pathogenic	0.72
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Benign	0.61	D
PhyloP100		0.91
GERP RS		2.5
PromoterAI		-0.26	Neutral
Mutation Taster		=19/81	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.92
SpliceAI score (max)		0.94		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.94		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs200764174; hg19: chr12-8975310;