chr15-89317531-A-G
Variant summary
Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PP3_ModeratePP5
The NM_002693.3(POLG):c.3488T>C(p.Met1163Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,874 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M1163R) has been classified as Uncertain significance.
Frequency
Consequence
NM_002693.3 missense
Scores
Clinical Significance
Conservation
Publications
- progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
- mitochondrial DNA depletion syndrome 4aInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet, G2P
- sensory ataxic neuropathy, dysarthria, and ophthalmoparesisInheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P
- autosomal dominant progressive external ophthalmoplegiaInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- autosomal recessive progressive external ophthalmoplegiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- mitochondrial neurogastrointestinal encephalomyopathyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- recessive mitochondrial ataxia syndromeInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- spinocerebellar ataxia with epilepsyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Leigh syndromeInheritance: AR Classification: LIMITED Submitted by: ClinGen
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ACMG classification
Our verdict: Likely_pathogenic. The variant received 7 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152168Hom.: 0 Cov.: 32 show subpopulations
GnomAD4 exome AF: 0.00000137 AC: 2AN: 1461706Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 727176 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152168Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74336 show subpopulations
ClinVar
Submissions by phenotype
not provided Pathogenic:1Uncertain:1
POLG: PM2, PM5:Supporting, PP3 -
p.Met1163Thr (ATG>ACG):c.3488 T>C in exon 22 of the POLG gene (NM_002693.2). The Met1163Thr missense change has not been published as a mutation, nor has it been reported as a benign polymorphism to our knowledge. The NHLBI ESP Exome Variant Project has not identified Met1163Thr in approximately 6,500 individuals of European or African American ethnicity, indicating that it is not a common benign variant in these populations. The amino acid substitution is non-conservative as a non-polar Methionine residue is replaced by a polar Threonine residue. It alters a conserved position in the protein and multiple in silico algorithms predict that Met1163Thr may be damaging to the structure/function of the protein. A different missense substitution at the same codon (Met1163Arg) was identified in a patient with progressive encephalopathy (Kolberg et al., 2006) and other missense mutations at neighboring codons in the polymerase domain of the protein (N1157S, S1176L) have been reported in association with POLG-related disorders. Therefore, based on the currently available information, Met1163Thr is a strong candidate for a disease-causing mutation, although the possibility that it is a benign variant cannot be excluded. The variant is found in INFANT-EPI panel(s). -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at