rs137852297

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 8P and 4B. PM1PM5PP3_StrongBS2

The NM_000273.3(GPR143):​c.695C>T​(p.Thr232Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000849 in 1,178,058 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 3 hemizygotes in GnomAD. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T232K) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000018 ( 0 hom., 1 hem., cov: 24)
Exomes 𝑓: 0.0000075 ( 0 hom. 2 hem. )

Consequence

GPR143
NM_000273.3 missense

Scores

12
4
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3

Conservation

PhyloP100: 8.90
Variant links:
Genes affected
GPR143 (HGNC:20145): (G protein-coupled receptor 143) This gene encodes a protein that binds to heterotrimeric G proteins and is targeted to melanosomes in pigment cells. This protein is thought to be involved in intracellular signal transduction mechanisms. Mutations in this gene cause ocular albinism type 1, also referred to as Nettleship-Falls type ocular albinism, a severe visual disorder. A related pseudogene has been identified on chromosome Y. [provided by RefSeq, Dec 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000273.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chrX-9743637-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 10518.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.97
BS2
High Hemizygotes in GnomAdExome4 at 2 XL gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GPR143NM_000273.3 linkc.695C>T p.Thr232Met missense_variant Exon 6 of 9 ENST00000467482.6 NP_000264.2 P51810
GPR143XM_005274541.4 linkc.695C>T p.Thr232Met missense_variant Exon 6 of 9 XP_005274598.1
GPR143XM_024452388.2 linkc.443C>T p.Thr148Met missense_variant Exon 6 of 9 XP_024308156.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GPR143ENST00000467482.6 linkc.695C>T p.Thr232Met missense_variant Exon 6 of 9 1 NM_000273.3 ENSP00000417161.1 P51810
GPR143ENST00000447366.5 linkc.443C>T p.Thr148Met missense_variant Exon 6 of 8 3 ENSP00000390546.2 H7BZN6
GPR143ENST00000431126.1 linkc.443C>T p.Thr148Met missense_variant Exon 6 of 6 3 ENSP00000406138.1 C9J9N1

Frequencies

GnomAD3 genomes
AF:
0.0000178
AC:
2
AN:
112256
Hom.:
0
Cov.:
24
AF XY:
0.0000290
AC XY:
1
AN XY:
34426
show subpopulations
Gnomad AFR
AF:
0.0000648
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.00000545
AC:
1
AN:
183486
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
67920
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:
0.0000122
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000751
AC:
8
AN:
1065802
Hom.:
0
Cov.:
26
AF XY:
0.00000596
AC XY:
2
AN XY:
335384
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000284
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000332
Gnomad4 SAS exome
AF:
0.0000749
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000246
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000178
AC:
2
AN:
112256
Hom.:
0
Cov.:
24
AF XY:
0.0000290
AC XY:
1
AN XY:
34426
show subpopulations
Gnomad4 AFR
AF:
0.0000648
Gnomad4 AMR
AF:
0.00
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:
0.0000264
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1
Jun 20, 2019
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 232 of the GPR143 protein (p.Thr232Met). This variant is present in population databases (rs137852297, gnomAD 0.001%). This missense change has been observed in individual(s) with clinical features of ocular albinism (internal data). ClinVar contains an entry for this variant (Variation ID: 1213617). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GPR143 protein function with a positive predictive value of 95%. This variant disrupts the p.Thr232 amino acid residue in GPR143. Other variant(s) that disrupt this residue have been observed in individuals with GPR143-related conditions (PMID: 9529334), which suggests that this may be a clinically significant amino acid residue. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Ocular albinism, type I Uncertain:1
Feb 22, 2024
3billion
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). Predicted Consequence/Location: Missense variant In silico tool predictions suggest damaging effect of the variant on gene or gene product [REVEL: 0.95 (>=0.6, sensitivity 0.68 and specificity 0.92); 3Cnet: 0.37 (>=0.6, sensitivity 0.72 and precision 0.9)]. A different missense change at the same codon (p.Thr232Lys) has been reported to be associated with GPR143 related disorder (ClinVar ID: VCV000010518 /PMID: 9529334). Therefore, this variant is classified as VUS according to the recommendation of ACMG/AMP guideline. -

Inborn genetic diseases Uncertain:1
Sep 01, 2021
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.695C>T (p.T232M) alteration is located in exon 6 (coding exon 6) of the GPR143 gene. This alteration results from a C to T substitution at nucleotide position 695, causing the threonine (T) at amino acid position 232 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.53
BayesDel_addAF
Pathogenic
0.66
D
BayesDel_noAF
Pathogenic
0.72
CADD
Pathogenic
26
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.97
D;.;D
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.95
D;D;D
M_CAP
Pathogenic
0.73
D
MetaRNN
Pathogenic
0.97
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.5
M;.;.
PrimateAI
Uncertain
0.65
T
PROVEAN
Pathogenic
-5.1
D;.;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;.;D
Sift4G
Pathogenic
0.0
D;D;.
Polyphen
1.0
D;.;.
Vest4
0.78
MutPred
0.81
Gain of helix (P = 0.0325);.;.;
MVP
0.99
MPC
0.29
ClinPred
0.99
D
GERP RS
5.2
Varity_R
0.85
gMVP
0.83

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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: rs137852297; hg19: chrX-9711677; COSMIC: COSV66632168; COSMIC: COSV66632168; API