chr12-89525174-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_172240.3(POC1B):​c.46G>A​(p.Gly16Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,613,418 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. G16V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

POC1B
NM_172240.3 missense

Scores

6
8
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.29
Variant links:
Genes affected
POC1B (HGNC:30836): (POC1 centriolar protein B) POC1 proteins contain an N-terminal WD40 domain and a C-terminal coiled coil domain and are part of centrosomes. They play an important role in basal body and cilia formation. This gene encodes one of the two POC1 proteins found in humans. Mutation in this gene result in autosomal-recessive cone-rod dystrophy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2014]
POC1B-GALNT4 (HGNC:42957): (POC1B-GALNT4 readthrough) This locus represents naturally occurring transcripts that splice the 5' exons of the POC1B (POC1 centriolar protein homolog B) gene on chromosome 12 to the GALNT4 (UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 4) gene, which is located within a POC1B intron. Alternative splicing results in two transcript variants, one of which encodes a fusion isoform that shares sequence identity with the products of each individual gene. [provided by RefSeq, Dec 2010]
POC1B-AS1 (HGNC:52949): (POC1B antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.774

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POC1BNM_172240.3 linkc.46G>A p.Gly16Ser missense_variant Exon 2 of 12 ENST00000313546.8 NP_758440.1 Q8TC44-1A0MNP0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POC1BENST00000313546.8 linkc.46G>A p.Gly16Ser missense_variant Exon 2 of 12 1 NM_172240.3 ENSP00000323302.3 Q8TC44-1
POC1B-GALNT4ENST00000548729.5 linkc.46G>A p.Gly16Ser missense_variant Exon 2 of 3 2 ENSP00000447852.1 F8VUJ3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152234
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000399
AC:
1
AN:
250376
Hom.:
0
AF XY:
0.00000739
AC XY:
1
AN XY:
135394
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000164
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461184
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
726922
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
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:
0.00000540
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152234
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74392
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cone-rod dystrophy 20 Uncertain:1
Mar 20, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Uncertain:1
Aug 22, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant has not been reported in the literature in individuals affected with POC1B-related conditions. This variant is present in population databases (rs780295968, gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 16 of the POC1B protein (p.Gly16Ser). 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 disruptive. 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
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Uncertain
0.12
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Benign
0.23
T;.;.
Eigen
Uncertain
0.68
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Benign
0.67
D
LIST_S2
Pathogenic
0.98
D;D;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.77
D;D;D
MetaSVM
Uncertain
0.59
D
PROVEAN
Pathogenic
-4.8
D;N;D
REVEL
Uncertain
0.62
Sift
Uncertain
0.0050
D;D;D
Sift4G
Uncertain
0.0040
D;T;D
Polyphen
1.0
D;D;.
Vest4
0.63
MutPred
0.46
Gain of loop (P = 0.0312);Gain of loop (P = 0.0312);Gain of loop (P = 0.0312);
MVP
0.92
MPC
0.38
ClinPred
0.98
D
GERP RS
4.6
Varity_R
0.71
gMVP
0.44

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs780295968; hg19: chr12-89918951; API