chr3-71772750-G-A

Position:

• chr3-71772750-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_001126128.2(PROK2):​c.364C>T​(p.Arg122*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,798 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 (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: PROK2 NM_001126128.2 stop_gained
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.15

Genes affected

PROK2 (HGNC:18455): (prokineticin 2) This gene encodes a protein expressed in the suprachiasmatic nucleus (SCN) circadian clock that may function as the output component of the circadian clock. The secreted form of the encoded protein may also serve as a chemoattractant for neuronal precursor cells in the olfactory bulb. Proteins from other vertebrates which are similar to this gene product were isolated based on homology to snake venom and secretions from frog skin, and have been shown to have diverse functions. Mutations in this gene are associated with Kallmann syndrome 4. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0667 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PROK2	NM_001126128.2	c.364C>T	p.Arg122*	stop_gained	4/4	ENST00000295619.4	NP_001119600.1
PROK2	NM_021935.4	c.301C>T	p.Arg101*	stop_gained	3/3		NP_068754.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PROK2	ENST00000295619.4	c.364C>T	p.Arg122*	stop_gained	4/4	1	NM_001126128.2	ENSP00000295619.3
PROK2	ENST00000353065.7	c.301C>T	p.Arg101*	stop_gained	3/3	1		ENSP00000295618.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251462 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135902

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461798 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727206

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 05, 2021

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. This premature translational stop signal has been observed in individual(s) with Kallmann syndrome (PMID: 24031091). This variant is present in population databases (rs751742071, ExAC 0.009%). This sequence change creates a premature translational stop signal (p.Arg122*) in the PROK2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 8 amino acid(s) of the PROK2 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Uncertain	0.91	D
Vest4		0.47
GERP RS		5.9

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: rs751742071; hg19: chr3-71821901;