NM_000939.4:c.668T>C

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BS1_Supporting

The NM_000939.4(POMC):c.668T>C(p.Met223Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000031 in 1,613,112 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (no stars).

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

POMC
NM_000939.4 missense

Scores

Clinical Significance

Uncertain significance no assertion criteria provided U:1

Conservation

PhyloP100: 5.54

Publications

5 publications found

Variant links:

Genes affected

POMC (HGNC:9201): (proopiomelanocortin) This gene encodes a preproprotein that undergoes extensive, tissue-specific, post-translational processing via cleavage by subtilisin-like enzymes known as prohormone convertases. There are eight potential cleavage sites within the preproprotein and, depending on tissue type and the available convertases, processing may yield as many as ten biologically active peptides involved in diverse cellular functions. The encoded protein is synthesized mainly in corticotroph cells of the anterior pituitary where four cleavage sites are used; adrenocorticotrophin, essential for normal steroidogenesis and the maintenance of normal adrenal weight, and lipotropin beta are the major end products. In other tissues, including the hypothalamus, placenta, and epithelium, all cleavage sites may be used, giving rise to peptides with roles in pain and energy homeostasis, melanocyte stimulation, and immune modulation. These include several distinct melanotropins, lipotropins, and endorphins that are contained within the adrenocorticotrophin and beta-lipotropin peptides. The antimicrobial melanotropin alpha peptide exhibits antibacterial and antifungal activity. Mutations in this gene have been associated with early onset obesity, adrenal insufficiency, and red hair pigmentation. Alternatively spliced transcript variants encoding the same protein have been described. [provided by RefSeq, Jan 2016]

POMC Gene-Disease associations (from GenCC):

obesity due to pro-opiomelanocortin deficiency
Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, Ambry Genetics
inherited obesity
Inheritance: SD, AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics

POMC links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

BS1

Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000138 (21/151886) while in subpopulation AFR AF = 0.000508 (21/41340). AF 95% confidence interval is 0.00034. There are 0 homozygotes in GnomAd4. There are 7 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POMC	NM_000939.4 link	c.668T>C	p.Met223Thr	missense_variant	Exon 3 of 3	ENST00000395826.7	NP_000930.1	P01189
POMC	NM_001035256.3 link	c.668T>C	p.Met223Thr	missense_variant	Exon 4 of 4		NP_001030333.1	P01189
POMC	NM_001319204.2 link	c.668T>C	p.Met223Thr	missense_variant	Exon 4 of 4		NP_001306133.1	P01189
POMC	NM_001319205.2 link	c.668T>C	p.Met223Thr	missense_variant	Exon 3 of 3		NP_001306134.1	P01189

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POMC	ENST00000395826.7 link	c.668T>C	p.Met223Thr	missense_variant	Exon 3 of 3	2	NM_000939.4	ENSP00000379170.2		P01189

Frequencies

GnomAD3 genomes

AF:

0.000138

AC:

AN:

151886

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000508

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

GnomAD2 exomes

AF:

0.0000359

AC:

AN:

250566

AF XY:

0.0000295

show subpopulations

Gnomad AFR exome

AF:

0.000494

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000198

AC:

AN:

1461226

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726934

show subpopulations

African (AFR)

AF:

0.000807

AC:

AN:

33478

American (AMR)

AF:

0.0000224

AC:

AN:

44722

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26126

East Asian (EAS)

AF:

0.00

AC:

AN:

39696

South Asian (SAS)

AF:

0.00

AC:

AN:

86240

European-Finnish (FIN)

AF:

0.00

AC:

AN:

52916

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111912

Other (OTH)

AF:

0.0000166

AC:

AN:

60372

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.461

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

AF:

0.000138

AC:

AN:

151886

Hom.:

Cov.:

AF XY:

0.0000944

AC XY:

AN XY:

74170

show subpopulations

African (AFR)

AF:

0.000508

AC:

AN:

41340

American (AMR)

AF:

0.00

AC:

AN:

15270

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3468

East Asian (EAS)

AF:

0.00

AC:

AN:

5134

South Asian (SAS)

AF:

0.00

AC:

AN:

4810

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10596

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67954

Other (OTH)

AF:

0.00

AC:

AN:

2086

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.475

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.000166

Hom.:

Bravo

AF:

0.000151

ESP6500AA

AF:

0.000681

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000330

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

LINK: link

Submissions by phenotype

POMC-related disorder

Uncertain:1

Sep 16, 2024

PreventionGenetics, part of Exact Sciences

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

The POMC c.668T>C variant is predicted to result in the amino acid substitution p.Met223Thr. This variant was reported in the heterozygous state in a patient with severe obesity (Courbage et al. 2021. PubMed ID: 34097736). It was also observed in a cohort of obese individuals, and in vitro functional studies show strong evidence of loss of function (Table 3 and Supplemental Data Set, Shah et al. 2023. PubMed ID: 36864747). This variant is reported in 0.052% of alleles in individuals of African descent in gnomAD. Although we suspect that this variant may be pathogenic, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.71

BayesDel_addAF

Benign

-0.067

BayesDel_noAF

Uncertain

0.020

CADD

Uncertain

(source)

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.52

D;D;D;D;T

Eigen

Uncertain

0.57

Eigen_PC

Uncertain

0.48

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.97

D;.;.;.;D

M_CAP

Uncertain

0.089

MetaRNN

Uncertain

0.69

D;D;D;D;D

MetaSVM

Uncertain

0.36

MutationAssessor

Uncertain

2.7

M;M;M;M;.

PhyloP100

5.5

PrimateAI

Uncertain

0.74

PROVEAN

Pathogenic

-5.0

D;D;D;D;D

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0010

D;D;D;D;D

Sift4G

Pathogenic

0.0010

D;D;D;D;.

Polyphen

0.99

D;D;D;D;.

Vest4

0.64

MVP

0.98

MPC

0.47

ClinPred

0.58

GERP RS

3.9

Varity_R

0.77

gMVP

0.72

Mutation Taster

=47/53

disease causing

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

NM_000939.4:c.668T>C

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over