11-108301720-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PP3_Moderate

The NM_000051.4(ATM):c.5250G>T(p.Trp1750Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,613,470 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Uncertain significancein ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W1750L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: ATM NM_000051.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 8.19

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 17 uncertain in NM_000051.4
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.911

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ATM	NM_000051.4	c.5250G>T	p.Trp1750Cys	missense_variant	35/63	ENST00000675843.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ATM	ENST00000675843.1	c.5250G>T	p.Trp1750Cys	missense_variant	35/63		NM_000051.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152016 Hom.: 0 Cov.: 32

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461454 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 727060

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 152016 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74242

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: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 15, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 31, 2023	The p.W1750C variant (also known as c.5250G>T), located in coding exon 34 of the ATM gene, results from a G to T substitution at nucleotide position 5250. The tryptophan at codon 1750 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Ataxia-telangiectasia syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 29, 2023

This sequence change replaces tryptophan, which is neutral and slightly polar, with cysteine, which is neutral and slightly polar, at codon 1750 of the ATM protein (p.Trp1750Cys). This variant is not present in population databases (gnomAD no frequency). 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: 127404). 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. RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (Invitae). 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Nov 27, 2013

This variant is denoted ATM c.5250G>T at the cDNA level, p.Trp1750Cys (W1750C) at the protein level, and results in the change of a Tryptophan to a Cysteine (TGG>TGT). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. ATM Trp1750Cys was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This variant is a non-conservative substitution of a non-polar amino acid for a polar one, altering a position that is well conserved throughout evolution and is not located in a known functional domain. Multiple in silico algorithms predict that this variant may be damaging to protein structure and function. Based on currently available information, it is unclear whether ATM Trp1750Cys is a pathogenic variant or a rare benign variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.57
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.38
Cadd	Pathogenic	29
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.58	D;D
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.87	D;.
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.91	D;D
MetaSVM	Uncertain	0.46	D
MutationAssessor	Uncertain	2.8	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Pathogenic	-4.4	D;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0020	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;D
Vest4		0.80
MutPred		0.70		Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);
MVP		0.99
MPC		0.67
ClinPred		0.99	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.89
gMVP		0.73

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs587779845; hg19: chr11-108172447;