chr12-132677439-T-C
Variant summary
Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2
The NM_006231.4(POLE):c.725A>G(p.His242Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,822 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H242P) has been classified as Uncertain significance.
Frequency
Consequence
NM_006231.4 missense
Scores
Clinical Significance
Conservation
Publications
- POLE-related polyposis and colorectal cancer syndromeInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- colorectal cancer, susceptibility to, 12Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
- facial dysmorphism-immunodeficiency-livedo-short stature syndromeInheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
- intrauterine growth retardation, metaphyseal dysplasia, adrenal hypoplasia congenita, genital anomalies, and immunodeficiencyInheritance: AR Classification: STRONG Submitted by: G2P
- IMAGe syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Polymerase proofreading-related adenomatous polyposisInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Uncertain_significance. The variant received 2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152212Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.00000795 AC: 2AN: 251474 AF XY: 0.00000736 show subpopulations
GnomAD4 exome AF: 0.00000205 AC: 3AN: 1461610Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1AN XY: 727142 show subpopulations ⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152212Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1AN XY: 74368 show subpopulations
ClinVar
Submissions by phenotype
not provided Uncertain:2
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 242 of the POLE protein (p.His242Arg). This variant is present in population databases (rs767612904, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with POLE-related conditions. ClinVar contains an entry for this variant (Variation ID: 405799). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt POLE protein function with a negative predictive value of 80%. 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. -
Colorectal cancer, susceptibility to, 12 Uncertain:1
To our knowledge, this sequence variant has not been previously reported in the literature. The POLE c.725A>G variant has an overall allele frequency of 0.000004 in the gnomAD database (Genome Aggregation Database; gnomad.broadinstitute.org). This variant is in the exonuclease domain of the protein where other pathogenic sequence variants have been found. In silico analyses indicate this is an evolutionarily conserved residue. Thus, it is unknown at this time whether this variant increases cancer risk. -
Hereditary cancer-predisposing syndrome Uncertain:1
The p.H242R variant (also known as c.725A>G), located in coding exon 8 of the POLE gene, results from an A to G substitution at nucleotide position 725. The histidine at codon 242 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at