chr11-108259055-GC-CT

Variant names:

• chr11-108259055-GC-CT
• rs587781956
• NM_000051.4:c.2446_2447delGCinsCT

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_000051.4(ATM):​c.2446_2447delGCinsCT​(p.Ala816Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. The variant is present in control chromosomes in GnomAd MNV project. The variant allele was found at a frequency of 0.00000398 in 1 alleles, including 0 homozygotes. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A816V) has been classified as Uncertain significance.

• Frequency: GnomAD MNV: 𝑓 0.0000040 Genomes: not found (cov: 32)
• Consequence: ATM NM_000051.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 2.69
• Publications: 0 publications found

Genes affected

ATM (HGNC:795): (ATM serine/threonine kinase) The protein encoded by this gene belongs to the PI3/PI4-kinase family. This protein is an important cell cycle checkpoint kinase that phosphorylates; thus, it functions as a regulator of a wide variety of downstream proteins, including tumor suppressor proteins p53 and BRCA1, checkpoint kinase CHK2, checkpoint proteins RAD17 and RAD9, and DNA repair protein NBS1. This protein and the closely related kinase ATR are thought to be master controllers of cell cycle checkpoint signaling pathways that are required for cell response to DNA damage and for genome stability. Mutations in this gene are associated with ataxia telangiectasia, an autosomal recessive disorder. [provided by RefSeq, Aug 2010]

ATM Gene-Disease associations (from GenCC):

• hereditary breast carcinoma

  Inheritance: AD Classification: DEFINITIVE Submitted by: Ambry Genetics, ClinGen
• ataxia telangiectasia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, ClinGen, Laboratory for Molecular Medicine, Orphanet
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: MODERATE, LIMITED Submitted by: ClinGen, Ambry Genetics
• prostate cancer

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• sarcoma

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• familial ovarian cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• gastric carcinoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 41 uncertain in NM_000051.4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ATM	NM_000051.4	c.2446_2447delGCinsCT	p.Ala816Leu	missense_variant		ENST00000675843.1	NP_000042.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ATM	ENST00000675843.1	c.2446_2447delGCinsCT	p.Ala816Leu	missense_variant			NM_000051.4	ENSP00000501606.1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

GnomAD MNV AF: 0.00000398 AC: 1 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Mar 12, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2446_2447delGCinsCT variant (also known as p.A816L), located in coding exon 15 of the ATM gene, results from an in-frame deletion of GC and insertion of CT at nucleotide positions 2446 to 2447. This results in the substitution of the alanine residue for a leucine residue at codon 816, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be neutral by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Based on the available evidence, the clinical significance of this variant remains unclear. -

Mar 17, 2025

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces alanine with leucine at codon 816 of the ATM protein. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Ataxia-telangiectasia syndrome Uncertain:1

Jan 17, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 816 of the ATM protein (p.Ala816Leu). This variant is present in population databases (rs587781956, gnomAD 0.0004%). This variant has not been reported in the literature in individuals affected with ATM-related conditions. ClinVar contains an entry for this variant (Variation ID: 141714). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. -

ATM-related cancer predisposition Uncertain:1

Feb 09, 2023

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Mar 28, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Familial cancer of breast Uncertain:1

Aug 06, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.7

Splicing

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

Other links and lift over

dbSNP: rs587781956; hg19: chr11-108129782;