7-2513172-G-A

Variant names:

• chr7-2513172-G-A
• rs139214722
• NM_001166355.2:c.63G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_001166355.2(LFNG):​c.63G>A​(p.Trp21*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: LFNG NM_001166355.2 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.610
• Publications: 1 publications found

Genes affected

LFNG (HGNC:6560): (LFNG O-fucosylpeptide 3-beta-N-acetylglucosaminyltransferase) This gene is a member of the glycosyltransferase 31 gene family. Members of this gene family, which also includes the MFNG (GeneID: 4242) and RFNG (GeneID: 5986) genes, encode evolutionarily conserved glycosyltransferases that act in the Notch signaling pathway to define boundaries during embryonic development. While their genomic structure is distinct from other glycosyltransferases, these proteins have a fucose-specific beta-1,3-N-acetylglucosaminyltransferase activity that leads to elongation of O-linked fucose residues on Notch, which alters Notch signaling. The protein encoded by this gene is predicted to be a single-pass type II Golgi membrane protein but it may also be secreted and proteolytically processed like the related proteins in mouse and Drosophila (PMID: 9187150). Mutations in this gene have been associated with autosomal recessive spondylocostal dysostosis 3. [provided by RefSeq, May 2018]

LFNG Gene-Disease associations (from GenCC):

• spondylocostal dysostosis 3, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• autosomal recessive spondylocostal dysostosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 4 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LFNG	NM_001166355.2	c.63G>A	p.Trp21*	stop_gained	Exon 2 of 9		NP_001159827.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LFNG	ENST00000402506.5	c.63G>A	p.Trp21*	stop_gained	Exon 2 of 9	2		ENSP00000385764.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
CADD	Benign	1.2
DANN	Benign	0.95
Eigen	Benign	0.047
Eigen_PC	Benign	-0.37
FATHMM_MKL	Benign	0.031	N
PhyloP100		-0.61
Vest4		0.26
GERP RS		0.92
Mutation Taster		=141/59	disease causing (fs/PTC)

Splicing

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

Other links and lift over

dbSNP: rs139214722; hg19: chr7-2552806;