17-4948259-G-A

Position:

• chr17-4948259-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The ENST00000225655.6(PFN1):​c.132+4C>T variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000168 in 1,603,400 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000017 (1 hom.)
• Consequence: PFN1 ENST00000225655.6 splice_donor_region, intron
• Scores: Splicing: ADA: 0.6138
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.91

Genes affected

PFN1 (HGNC:8881): (profilin 1) This gene encodes a member of the profilin family of small actin-binding proteins. The encoded protein plays an important role in actin dynamics by regulating actin polymerization in response to extracellular signals. Deletion of this gene is associated with Miller-Dieker syndrome, and the encoded protein may also play a role in Huntington disease. Multiple pseudogenes of this gene are located on chromosome 1. [provided by RefSeq, Jul 2012]

ENO3 (HGNC:3354): (enolase 3) This gene encodes one of the three enolase isoenzymes found in mammals. This isoenzyme is found in skeletal muscle cells in the adult where it may play a role in muscle development and regeneration. A switch from alpha enolase to beta enolase occurs in muscle tissue during development in rodents. Mutations in this gene have be associated glycogen storage disease. Alternatively spliced transcript variants encoding different isoforms have been described.[provided by RefSeq, Jul 2010]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.38).
• BS2: High AC in GnomAdExome4 at 24 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PFN1	NM_005022.4	c.132+4C>T		splice_donor_region_variant, intron_variant		ENST00000225655.6	NP_005013.1
PFN1	NM_001375991.1	c.132+4C>T		splice_donor_region_variant, intron_variant			NP_001362920.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PFN1	ENST00000225655.6	c.132+4C>T		splice_donor_region_variant, intron_variant		1	NM_005022.4	ENSP00000225655	P1
ENO3	ENST00000519266.5	c.-91G>A		5_prime_UTR_variant	1/2	3		ENSP00000467270
ENO3	ENST00000520221.5	c.-117G>A		5_prime_UTR_variant	1/7	5		ENSP00000467444
PFN1	ENST00000572383.1	c.369+4C>T		splice_donor_region_variant, intron_variant		3		ENSP00000460363

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152180 Hom.: 0 Cov.: 33

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: 0.000413

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000292 AC: 7 AN: 239832 Hom.: 0 AF XY: 0.0000459 AC XY: 6 AN XY: 130600

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000301

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000170

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000914

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000165 AC: 24 AN: 1451220 Hom.: 1 Cov.: 35 AF XY: 0.0000263 AC XY: 19 AN XY: 722082

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000459

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000223

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000271

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152180 Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2 AN XY: 74354

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000413

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000189

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

Nov 23, 2022

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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. This variant has not been reported in the literature in individuals affected with PFN1-related conditions. This variant is present in population databases (rs755758083, gnomAD 0.02%). This sequence change falls in intron 1 of the PFN1 gene. It does not directly change the encoded amino acid sequence of the PFN1 protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.38
CADD	Benign	19
DANN	Benign	0.97
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.61
dbscSNV1_RF	Benign	0.58
SpliceAI score (max)		0.040		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: rs755758083; hg19: chr17-4851554;