2-85545521-A-G

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_000821.7(GGCX):c.*4413T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00402 in 152,348 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0040 (2 hom., cov: 33)
  • Failed GnomAD Quality Control
• Consequence: GGCX NM_000821.7 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.240

Genes affected

GGCX (HGNC:4247): (gamma-glutamyl carboxylase) This gene encodes an integral membrane protein of the rough endoplasmic reticulum that carboxylates glutamate residues of vitamin K-dependent proteins to gamma carboxyl glutamate, a modification that is required for their activity. The vitamin K-dependent protein substrates have a propeptide that binds the enzyme, with carbon dioxide, dioxide, and reduced vitamin K acting as co-substrates. Vitamin K-dependent proteins affect a number of physiologic processes including blood coagulation, prevention of vascular calcification, and inflammation. Allelic variants of this gene have been associated with pseudoxanthoma elasticum-like disorder with associated multiple coagulation factor deficiency. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2015]

ACMG classification

Verdict is Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00402 (613/152348) while in subpopulation NFE AF= 0.00767 (522/68038). AF 95% confidence interval is 0.00713. There are 2 homozygotes in gnomad4. There are 284 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High Homozygotes in GnomAd at 2 AD,AR,Digenic gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GGCX	NM_000821.7	c.*4413T>C		3_prime_UTR_variant	15/15	ENST00000233838.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GGCX	ENST00000233838.9	c.*4413T>C		3_prime_UTR_variant	15/15	1	NM_000821.7	P1

Frequencies

GnomAD3 genomes AF: 0.00403 AC: 613 AN: 152230 Hom.: 2 Cov.: 33

Gnomad AFR AF: 0.00111

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00183

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000827

Gnomad FIN AF: 0.000659

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00767

Gnomad OTH AF: 0.00287

GnomAD4 exome Data not reliable, filtered out with message: AC0 AC: 0 AN: 0 Hom.: 0 Cov.: 0 AC XY: 0 AN XY: 0

GnomAD4 genome AF: 0.00402 AC: 613 AN: 152348 Hom.: 2 Cov.: 33 AF XY: 0.00381 AC XY: 284 AN XY: 74510

Gnomad4 AFR AF: 0.00111

Gnomad4 AMR AF: 0.00183

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000828

Gnomad4 FIN AF: 0.000659

Gnomad4 NFE AF: 0.00767

Gnomad4 OTH AF: 0.00284

Alfa AF: 0.00584 Hom.: 0

Bravo AF: 0.00390

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Vitamin K-dependent clotting factors, combined deficiency of, type 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
Cadd	Benign	4.3
Dann	Benign	0.56

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: rs144074011; hg19: chr2-85772644;