1-193147940-G-C

Position:

• chr1-193147940-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_024529.5(CDC73):​c.803G>C​(p.Arg268Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,660 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R268Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CDC73 NM_024529.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.75

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, CDC73

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CDC73	NM_024529.5	c.803G>C	p.Arg268Pro	missense_variant	8/17	ENST00000367435.5
CDC73	XM_006711537.5	c.803G>C	p.Arg268Pro	missense_variant	8/11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CDC73	ENST00000367435.5	c.803G>C	p.Arg268Pro	missense_variant	8/17	1	NM_024529.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460660 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726770

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Parathyroid carcinoma Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 09, 2019

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CDC73-related conditions. ClinVar contains an entry for this variant (Variation ID: 462768). This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with proline at codon 268 of the CDC73 protein (p.Arg268Pro). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and proline. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 30, 2022

The p.R268P variant (also known as c.803G>C), located in coding exon 8 of the CDC73 gene, results from a G to C substitution at nucleotide position 803. The arginine at codon 268 is replaced by proline, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Uncertain	0.044	T
BayesDel_noAF	Benign	-0.17
CADD	Uncertain	24
DANN	Benign	0.97
DEOGEN2	Benign	0.31	T;T
Eigen	Uncertain	0.21
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Benign	0.038	D
MetaRNN	Uncertain	0.64	D;D
MetaSVM	Benign	-0.81	T
MutationAssessor	Benign	1.4	L;L
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.76	T
Polyphen		0.74	P;P
Vest4		0.51
MutPred		0.51		Gain of catalytic residue at R268 (P = 0.0222);Gain of catalytic residue at R268 (P = 0.0222);
MVP		0.55
MPC		1.5
ClinPred		0.85	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.24
gMVP		0.77

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

LitVar

Other links and lift over

dbSNP: rs750706815; hg19: chr1-193117070;