18-669101-CAA-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001071.4(TYMS):c.486_487del(p.Arg163SerfsTer3) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000342 in 1,461,840 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: TYMS NM_001071.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 7.06

Genes affected

TYMS (HGNC:12441): (thymidylate synthetase) Thymidylate synthase catalyzes the methylation of deoxyuridylate to deoxythymidylate using, 10-methylenetetrahydrofolate (methylene-THF) as a cofactor. This function maintains the dTMP (thymidine-5-prime monophosphate) pool critical for DNA replication and repair. The enzyme has been of interest as a target for cancer chemotherapeutic agents. It is considered to be the primary site of action for 5-fluorouracil, 5-fluoro-2-prime-deoxyuridine, and some folate analogs. Expression of this gene and that of a naturally occurring antisense transcript, mitochondrial enolase superfamily member 1 (GeneID:55556), vary inversely when cell-growth progresses from late-log to plateau phase. Polymorphisms in this gene may be associated with etiology of neoplasia, including breast cancer, and response to chemotherapy. [provided by RefSeq, Aug 2017]

ENOSF1 (HGNC:):

ACMG classification

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 18-669101-CAA-C is Pathogenic according to our data. Variant chr18-669101-CAA-C is described in ClinVar as [Pathogenic]. Clinvar id is 1693537.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr18-669101-CAA-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TYMS	NM_001071.4	c.486_487del	p.Arg163SerfsTer3	frameshift_variant	4/7	ENST00000323274.15

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TYMS	ENST00000323274.15	c.486_487del	p.Arg163SerfsTer3	frameshift_variant	4/7	1	NM_001071.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461840 Hom.: 0 AF XY: 0.00000275 AC XY: 2 AN XY: 727224

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Dyskeratosis congenita, digenic Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Sep 22, 2022

- -

Dyskeratosis congenita Pathogenic:1

Pathogenic, criteria provided, single submitter

research

Bone Marrow Failure laboratory, Queen Mary University London

Jun 22, 2022

This heterozygous frameshift variant of TYMS was identified in dyskeratosis congenita. The following ACMG/AMP criteria were used: PVS1, PS4_supporting, PM2_supporting, PP3 -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr18-669101;