Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate
The ENST00000456914.7(MUTYH):โc.1017_1035delโ(p.Arg340ProfsTer34) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000684 in 1,461,842 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (โ ). Synonymous variant affecting the same amino acid position (i.e. P339P) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.
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 12 ACMG points.
PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 1-45331727-TGGCAGAGCTCTCCTCCCTG-T is Pathogenic according to our data. Variant chr1-45331727-TGGCAGAGCTCTCCTCCCTG-T is described in ClinVar as [Pathogenic]. Clinvar id is 224537.Status of the report is criteria_provided_single_submitter, 1 stars.