chr8-67093606-A-G

Position:

• chr8-67093606-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001382391.1(CSPP1):​c.448A>G​(p.Ser150Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,380 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/18 in silico tools predict a benign outcome for this variant. 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. S150I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CSPP1 NM_001382391.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.35

Genes affected

CSPP1 (HGNC:26193): (centrosome and spindle pole associated protein 1) This gene encodes a centrosome and spindle pole associated protein. The encoded protein plays a role in cell-cycle progression and spindle organization, regulates cytokinesis, interacts with Nephrocystin 8 and is required for cilia formation. Mutations in this gene result in primary cilia abnormalities and classical Joubert syndrome. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Apr 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11149448).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CSPP1	NM_001382391.1	c.448A>G	p.Ser150Gly	missense_variant	6/31	ENST00000678616.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CSPP1	ENST00000678616.1	c.448A>G	p.Ser150Gly	missense_variant	6/31		NM_001382391.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460380 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 726656

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Joubert syndrome 21 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 20, 2017

This sequence change replaces serine with glycine at codon 159 of the CSPP1 protein (p.Ser159Gly). The serine residue is weakly conserved and there is a small physicochemical difference between serine and glycine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a CSPP1-related disease. 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. In summary, this variant is a novel missense change that is not predicted to affect protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.27	T
BayesDel_noAF	Benign	-0.63
CADD	Benign	17
DANN	Uncertain	0.98
DEOGEN2	Benign	0.031	T;.
Eigen	Benign	-0.34
Eigen_PC	Benign	-0.18
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Benign	0.75	T;T
M_CAP	Benign	0.0095	T
MetaRNN	Benign	0.11	T;T
MetaSVM	Benign	-0.99	T
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-2.1	N;N
REVEL	Benign	0.057
Sift	Benign	0.28	T;T
Sift4G	Benign	0.066	T;T
Polyphen		0.18	.;B
Vest4		0.29
MVP		0.24
MPC		0.13
ClinPred		0.40	T
GERP RS		2.5
gMVP		0.041

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: rs1554569071; hg19: chr8-68005841;