5-123346641-G-A

Variant names:

• chr5-123346641-G-A
• rs2126957635
• NM_001375405.1:c.2839C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001375405.1(CEP120):​c.2839C>T​(p.Arg947Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000753 in 1,461,682 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. R947H) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: CEP120 NM_001375405.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.29
• Publications: 0 publications found

Genes affected

CEP120 (HGNC:26690): (centrosomal protein 120) This gene encodes a protein that functions in the microtubule-dependent coupling of the nucleus and the centrosome. A similar protein in mouse plays a role in both interkinetic nuclear migration, which is a characteristic pattern of nuclear movement in neural progenitors, and in neural progenitor self-renewal. Mutations in this gene are predicted to result in neurogenic defects. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2009]

CEP120 Gene-Disease associations (from GenCC):

• ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• Joubert syndrome 31

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• short-rib thoracic dysplasia 13 with or without polydactyly

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• Jeune syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome with ocular defect

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CEP120	NM_001375405.1	c.2839C>T	p.Arg947Cys	missense_variant	Exon 20 of 20	ENST00000306467.10	NP_001362334.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CEP120	ENST00000306467.10	c.2839C>T	p.Arg947Cys	missense_variant	Exon 20 of 20	5	NM_001375405.1	ENSP00000303058.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000753 AC: 11 AN: 1461682 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 727142

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44678

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39684

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53404

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000899 AC: 10 AN: 1111906

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Short-rib thoracic dysplasia 13 with or without polydactyly Uncertain:1

Sep 21, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 947 of the CEP120 protein (p.Arg947Cys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CEP120-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CEP120 protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.48
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.14
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.17	T;T;.
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	.;D;D
M_CAP	Benign	0.052	D
MetaRNN	Uncertain	0.62	D;D;D
MetaSVM	Benign	-0.71	T
MutationAssessor	Benign	2.0	M;M;.
PhyloP100		6.3
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-5.1	D;D;D
REVEL	Uncertain	0.45
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.71
MutPred		0.46		Gain of catalytic residue at L948 (P = 0.009);Gain of catalytic residue at L948 (P = 0.009);.;
MVP		0.45
MPC		0.50
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.59
gMVP		0.61
Mutation Taster		=62/38	polymorphism

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

Other links and lift over

dbSNP: rs2126957635; hg19: chr5-122682335;