Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong
The NM_001048174.2(MUTYH):āc.563G>Cā(p.Gly188Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G188E) has been classified as Likely pathogenic.
MUTYH (HGNC:7527): (mutY DNA glycosylase) This gene encodes a DNA glycosylase involved in oxidative DNA damage repair. The enzyme excises adenine bases from the DNA backbone at sites where adenine is inappropriately paired with guanine, cytosine, or 8-oxo-7,8-dihydroguanine, a major oxidatively damaged DNA lesion. The protein is localized to the nucleus and mitochondria. This gene product is thought to play a role in signaling apoptosis by the introduction of single-strand breaks following oxidative damage. Mutations in this gene result in heritable predisposition to colorectal cancer, termed MUTYH-associated polyposis (MAP). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2017]
Verdict is Pathogenic. Variant got 10 ACMG points.
PM1
In a helix (size 16) in uniprot entity MUTYH_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_001048174.2
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-45332617-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 231491.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=5, Uncertain_significance=3}.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.989