1-193130173-G-T

Variant names:

• chr1-193130173-G-T
• rs587776559
• NM_024529.5:c.238-1G>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_024529.5(CDC73):​c.238-1G>T variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000071 in 1,408,978 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: CDC73 NM_024529.5 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.60
• Publications: 0 publications found

Genes affected

CDC73 (HGNC:16783): (cell division cycle 73) This gene encodes a tumor suppressor that is involved in transcriptional and post-transcriptional control pathways. The protein is a component of the the PAF protein complex, which associates with the RNA polymerase II subunit POLR2A and with a histone methyltransferase complex. This protein appears to facilitate the association of 3' mRNA processing factors with actively-transcribed chromatin. Mutations in this gene have been linked to hyperparathyroidism-jaw tumor syndrome, familial isolated hyperparathyroidism, and parathyroid carcinoma. [provided by RefSeq, Jul 2009]

CDC73 Gene-Disease associations (from GenCC):

• hyperparathyroidism 2 with jaw tumors

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Ambry Genetics
• hyperparathyroidism 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• parathyroid gland carcinoma

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial isolated hyperparathyroidism

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000308280 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-193130173-G-T is Pathogenic according to our data. Variant chr1-193130173-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1790454.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDC73	NM_024529.5	c.238-1G>T		splice_acceptor_variant, intron_variant	Intron 2 of 16	ENST00000367435.5	NP_078805.3
CDC73	XM_006711537.5	c.238-1G>T		splice_acceptor_variant, intron_variant	Intron 2 of 10		XP_006711600.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDC73	ENST00000367435.5	c.238-1G>T		splice_acceptor_variant, intron_variant	Intron 2 of 16	1	NM_024529.5	ENSP00000356405.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.10e-7 AC: 1 AN: 1408978 Hom.: 0 Cov.: 25 AF XY: 0.00000142 AC XY: 1 AN XY: 704492

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 32480

American (AMR) AF: 0.00 AC: 0 AN: 44652

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25812

East Asian (EAS) AF: 0.00 AC: 0 AN: 39390

South Asian (SAS) AF: 0.0000117 AC: 1 AN: 85134

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52966

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5478

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1064498

Other (OTH) AF: 0.00 AC: 0 AN: 58568

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1

Sep 24, 2020

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.238-1G>T intronic variant results from a G to T substitution one nucleotide upstream from coding exon 3 of the CDC73 gene. In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site and will result in the creation or strengthening of a novel splice acceptor site. Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.6
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.58		Position offset: 24
DS_AL_spliceai		0.97		Position offset: 1

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

Other links and lift over

dbSNP: rs587776559; hg19: chr1-193099303;