rs121908828

Positions:

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PM5PP3_Moderate

The NM_017849.4(TMEM127):c.419G>T(p.Cys140Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,854 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. C140R) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TMEM127
NM_017849.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 7.41

Variant links:

Genes affected

TMEM127 (HGNC:26038): (transmembrane protein 127) This gene encodes a transmembrane protein with four predicted transmembrane domains. The protein is associated with a subpopulation of vesicular organelles corresponding to early endosomal structures, with the Golgi, and with lysosomes, and may participate in protein trafficking between these structures. Mutations in this gene and several other genes cause pheochromocytomas. Alternatively spliced transcript variants encoding the same protein have been identified. [provided by RefSeq, Aug 2022]

TMEM127 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM1

In a chain Transmembrane protein 127 (size 237) in uniprot entity TM127_HUMAN there are 6 pathogenic changes around while only 2 benign (75%) in NM_017849.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr2-96254107-A-G is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.923

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TMEM127	NM_017849.4 linkuse as main transcript	c.419G>T	p.Cys140Phe	missense_variant	4/4	ENST00000258439.8	NP_060319.1	O75204
TMEM127	NM_001193304.3 linkuse as main transcript	c.419G>T	p.Cys140Phe	missense_variant	4/4		NP_001180233.1	O75204
TMEM127	NM_001407282.1 linkuse as main transcript	c.167G>T	p.Cys56Phe	missense_variant	3/3		NP_001394211.1
TMEM127	NM_001407283.1 linkuse as main transcript	c.167G>T	p.Cys56Phe	missense_variant	3/3		NP_001394212.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
TMEM127	ENST00000258439.8 linkuse as main transcript	c.419G>T	p.Cys140Phe	missense_variant	4/4	1	NM_017849.4	ENSP00000258439.3	O75204
TMEM127	ENST00000432959.1 linkuse as main transcript	c.419G>T	p.Cys140Phe	missense_variant	4/4	1		ENSP00000416660.1	O75204
TMEM127	ENST00000435268.1 linkuse as main transcript	c.167G>T	p.Cys56Phe	missense_variant	3/3	3		ENSP00000411810.1	C9J4H2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152176

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461678

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727158

show subpopulations

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152176

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74328

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 02, 2024

The p.C140F variant (also known as c.419G>T), located in coding exon 3 of the TMEM127 gene, results from a G to T substitution at nucleotide position 419. The cysteine at codon 140 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary pheochromocytoma-paraganglioma

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 02, 2017

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 disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This particular variant has not been reported in the literature in individuals with TMEM127-related disease, but two different changes affecting the same codon (p.Cys140Tyr and p.Cys140Arg) have been reported in individuals affected with pheochromocytoma (PMID: 26960314, 21156949, 22517554). This variant is not present in population databases (ExAC no frequency). This sequence change replaces cysteine with phenylalanine at codon 140 of the TMEM127 protein (p.Cys140Phe). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and phenylalanine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.99

BayesDel_addAF

Pathogenic

0.41

BayesDel_noAF

Pathogenic

0.35

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Benign

0.31

T;T;.

Eigen

Pathogenic

0.73

Eigen_PC

Pathogenic

0.76

FATHMM_MKL

Pathogenic

1.0

LIST_S2

Uncertain

0.89

.;D;D

M_CAP

Uncertain

0.13

MetaRNN

Pathogenic

0.92

D;D;D

MetaSVM

Uncertain

0.28

MutationAssessor

Uncertain

2.0

M;M;.

PrimateAI

Pathogenic

0.93

PROVEAN

Pathogenic

-7.3

D;D;D

REVEL

Pathogenic

0.86

Sift

Uncertain

0.0040

D;D;D

Sift4G

Pathogenic

0.0

D;D;D

Polyphen

1.0

D;D;.

Vest4

0.88

MutPred

0.80

Gain of helix (P = 0.0696);Gain of helix (P = 0.0696);.;

MVP

0.82

MPC

1.6

ClinPred

0.99

GERP RS

5.9

Varity_R

0.86

gMVP

0.96

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over