11-108330261-T-C
Variant summary
Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PP3PM2_SupportingPM3_StrongPS3_Supporting
This summary comes from the ClinGen Evidence Repository: The c.7355T>C variant in ATM is a missense variant predicted to cause substitution of leucine by proline at amino acid 2452 (p.Leu2452Pro). This variant has been detected in at least two individuals with Ataxia-Telangiectasia (PMIDs: 19431188, 26896183). The highest population minor allele frequency in gnomAD v4.1.0 is 0.000001695 in the European (non-Finnish) population, which is lower than the HBOP threshold (≤0.00001) for PM2_Supporting, meeting this criterion. Western blotting in ATM null cells transfected with cDNA carrying this variant showed inactive phosphorylation of ATM downstream targets as compared to wild-type controls, indicating that this variant impacts protein function (PMID:19431188). The computational predictor REVEL gives a score of 0.914, which is above the threshold of 0.733, evidence that correlates with impact to ATM function. In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal dominant ATM-related cancer predisposition and autosomal recessive Ataxia-Telangiectasia based on the ACMG/AMP criteria applied as specified by the HBOP VCEP. (PM3_Strong, PM2_Supporting, PS3_Supporting, PP3) LINK:https://erepo.genome.network/evrepo/ui/classification/CA382559953/MONDO:0700270/020
Frequency
Consequence
NM_000051.4 missense
Scores
Clinical Significance
Conservation
Publications
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ACMG classification
Our verdict: Likely_pathogenic. The variant received 7 ACMG points.
Variant Effect in Transcripts
ACMG analysis was done for transcript: NM_000051.4. You can select a different transcript below to see updated ACMG assignments.
RefSeq Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| ATM | NM_000051.4 | MANE Select | c.7355T>C | p.Leu2452Pro | missense | Exon 50 of 63 | NP_000042.3 | ||
| ATM | NM_001351834.2 | c.7355T>C | p.Leu2452Pro | missense | Exon 51 of 64 | NP_001338763.1 | |||
| C11orf65 | NM_001330368.2 | c.641-21190A>G | intron | N/A | NP_001317297.1 |
Ensembl Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| ATM | ENST00000675843.1 | MANE Select | c.7355T>C | p.Leu2452Pro | missense | Exon 50 of 63 | ENSP00000501606.1 | ||
| ATM | ENST00000452508.7 | TSL:1 | c.7355T>C | p.Leu2452Pro | missense | Exon 51 of 64 | ENSP00000388058.2 | ||
| ATM | ENST00000527805.6 | TSL:1 | n.*2419T>C | non_coding_transcript_exon | Exon 48 of 61 | ENSP00000435747.2 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 exome AF: 0.00000137 AC: 2AN: 1461842Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0AN XY: 727222 show subpopulations
Age Distribution
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Hereditary cancer-predisposing syndrome Pathogenic:2
This missense variant replaces leucine with proline at codon 2452 of the ATM protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). Functional studies have shown that this variant disrupted kinase activity (PMID: 19431188, 26896183). This variant has been observed in two individuals affected with autosomal recessive ataxia-telangiectasia, one of which was confirmed in the compound heterozygous state with a second pathogenic variant, indicating that this variant contributes to disease (PMID: 19431188, 26896183). This variant was also detected in a breast cancer case-control analysis (PMID: 21787400). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Likely Pathogenic.
The p.L2452P variant (also known as c.7355T>C), located in coding exon 49 of the ATM gene, results from a T to C substitution at nucleotide position 7355. The leucine at codon 2452 is replaced by proline, an amino acid with similar properties. This alteration was identified in a patient with ataxia telangiectasia in conjunction with another ATM alteration, c.7638_7646del9 (Jackson TJ et al. Dev Med Child Neurol. 2016 07;58:690-7). In a functional study, this alteration showed loss of kinase activity (Barone G et al. Hum. Mutat. 2009 Aug;30:1222-30). This alteration has also been identified in 1 of 2570 Caucasian breast cancer cases and 0 of 1448 controls (Goldgar DE et al. Breast Cancer Res. 2011 Jul;13:R73). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the majority of available evidence to date, this variant is likely to be pathogenic.
Ataxia-telangiectasia syndrome Uncertain:2
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.
This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 2452 of the ATM protein (p.Leu2452Pro). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with ataxia-telangiectasia (PMID: 19431188, 26896183). ClinVar contains an entry for this variant (Variation ID: 481101). 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 disruptive. Experimental studies have shown that this missense change affects ATM function (PMID: 19431188). 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 Pathogenic:1
The c.7355T>C variant in ATM is a missense variant predicted to cause substitution of leucine by proline at amino acid 2452 (p.Leu2452Pro). This variant has been detected in at least two individuals with Ataxia-Telangiectasia (PMIDs: 19431188, 26896183). The highest population minor allele frequency in gnomAD v4.1.0 is 0.000001695 in the European (non-Finnish) population, which is lower than the HBOP threshold (≤0.00001) for PM2_Supporting, meeting this criterion. Western blotting in ATM null cells transfected with cDNA carrying this variant showed inactive phosphorylation of ATM downstream targets as compared to wild-type controls, indicating that this variant impacts protein function (PMID: 19431188). The computational predictor REVEL gives a score of 0.914, which is above the threshold of 0.733, evidence that correlates with impact to ATM function. In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal dominant ATM-related cancer predisposition and autosomal recessive Ataxia-Telangiectasia based on the ACMG/AMP criteria applied as specified by the HBOP VCEP. (PM3_Strong, PM2_Supporting, PS3_Supporting, PP3)
not specified Uncertain:1
Variant summary: ATM c.7355T>C (p.Leu2452Pro) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251270 control chromosomes (gnomAD). c.7355T>C has been reported in the literature as a compound heterozygous genotype in at least one individual affected with Ataxia-Telangiectasia and has been found in at least one individual undergoing ATM sequencing for breast cancer risk (e.g. Barone_2009, Jackson_2016, Goldgar_2011). These report(s) do not provide unequivocal conclusions about association of the variant with disease. At least one publication reports experimental evidence evaluating an impact on protein function. It was found that the variant ATM protein had little to no detectable kinase activity toward downstream targets in an expression model system (e.g. Barone_2009). Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS - possibly pathogenic.
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at