Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1PP5_Moderate
The NM_024757.5(EHMT1):c.3181-80_3233del(p.Tyr1061fs) variant causes a frameshift, splice acceptor, splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. Y1061Y) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.
EHMT1 (HGNC:24650): (euchromatic histone lysine methyltransferase 1) The protein encoded by this gene is a histone methyltransferase that methylates the lysine-9 position of histone H3. This action marks the genomic region packaged with these methylated histones for transcriptional repression. This protein may be involved in the silencing of MYC- and E2F-responsive genes and therefore could play a role in the G0/G1 cell cycle transition. Defects in this gene are a cause of chromosome 9q subtelomeric deletion syndrome (9q-syndrome, also known as Kleefstra syndrome). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2017]
EHMT1 Gene-Disease associations (from GenCC):
Kleefstra syndrome
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
Our verdict: Pathogenic. The variant received 10 ACMG points.
PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 9-137814350-CTGGAAGACGTAGTTGTGACTGGGAGGGGAAATGGAAGGCCTGTGCCTGCACGTCTGACCCCCCGGCGCCTCTCTTCTCAGTACTGCGTGTGCATCGACGACTGCTCCTCCAGCAACTGCATGTGCGGCCAGCT-C is Pathogenic according to our data. Variant chr9-137814350-CTGGAAGACGTAGTTGTGACTGGGAGGGGAAATGGAAGGCCTGTGCCTGCACGTCTGACCCCCCGGCGCCTCTCTTCTCAGTACTGCGTGTGCATCGACGACTGCTCCTCCAGCAACTGCATGTGCGGCCAGCT-C is described in ClinVar as Pathogenic. ClinVar VariationId is 41267.Status of the report is criteria_provided_single_submitter, 1 stars.