4-78364055-G-T

Position:

• chr4-78364055-G-T

Variant summary

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

The NM_025074.7(FRAS1):​c.2722+1G>T variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000632 in 1,424,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000063 (0 hom.)
• Consequence: FRAS1 NM_025074.7 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.57

Genes affected

FRAS1 (HGNC:19185): (Fraser extracellular matrix complex subunit 1) This gene encodes an extracellular matrix protein that appears to function in the regulation of epidermal-basement membrane adhesion and organogenesis during development. Mutations in this gene cause Fraser syndrome, a multisystem malformation that can include craniofacial, urogenital and respiratory system abnormalities. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.012127253 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FRAS1	NM_025074.7	c.2722+1G>T		splice_donor_variant		ENST00000512123.4	NP_079350.5
FRAS1	NM_001166133.2	c.2722+1G>T		splice_donor_variant			NP_001159605.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FRAS1	ENST00000512123.4	c.2722+1G>T		splice_donor_variant		5	NM_025074.7	ENSP00000422834	P1
FRAS1	ENST00000325942.11	c.2722+1G>T		splice_donor_variant		1		ENSP00000326330
FRAS1	ENST00000682513.1	c.2722+1G>T		splice_donor_variant				ENSP00000508201
FRAS1	ENST00000684159.1	c.2722+1G>T		splice_donor_variant				ENSP00000506875

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000632 AC: 9 AN: 1424878 Hom.: 0 Cov.: 31 AF XY: 0.00000709 AC XY: 5 AN XY: 705110

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: 0.0000369

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000366

Gnomad4 OTH exome AF: 0.0000338

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.97	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.6

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.80		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.80		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs794727365; hg19: chr4-79285209;