13-39655677-G-A

Variant names:

• chr13-39655677-G-A
• rs1442379324
• NM_020751.3:c.-50G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_020751.3(COG6):​c.-50G>A variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000214 in 1,401,834 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COG6 NM_020751.3 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.395
• Publications: 0 publications found

Genes affected

COG6 (HGNC:18621): (component of oligomeric golgi complex 6) This gene encodes a subunit of the conserved oligomeric Golgi complex that is required for maintaining normal structure and activity of the Golgi apparatus. The encoded protein is organized with conserved oligomeric Golgi complex components 5, 7 and 8 into a sub-complex referred to as lobe B. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Feb 2009]

COG6 Gene-Disease associations (from GenCC):

• COG6-congenital disorder of glycosylation

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet, Labcorp Genetics (formerly Invitae)
• hypohidrosis-enamel hypoplasia-palmoplantar keratoderma-intellectual disability syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.006).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COG6	NM_020751.3	c.-50G>A		5_prime_UTR_premature_start_codon_gain_variant	Exon 1 of 19	ENST00000455146.8	NP_065802.1
COG6	NM_020751.3	c.-50G>A		5_prime_UTR_variant	Exon 1 of 19	ENST00000455146.8	NP_065802.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COG6	ENST00000455146.8	c.-50G>A		5_prime_UTR_premature_start_codon_gain_variant	Exon 1 of 19	1	NM_020751.3	ENSP00000397441.2
COG6	ENST00000455146.8	c.-50G>A		5_prime_UTR_variant	Exon 1 of 19	1	NM_020751.3	ENSP00000397441.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD2 exomes AF: 0.00000634 AC: 1 AN: 157654 AF XY: 0.0000118

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000841

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000214 AC: 3 AN: 1401834 Hom.: 0 Cov.: 30 AF XY: 0.00000289 AC XY: 2 AN XY: 692396

African (AFR) AF: 0.00 AC: 0 AN: 31700

American (AMR) AF: 0.00 AC: 0 AN: 37380

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25272

East Asian (EAS) AF: 0.0000277 AC: 1 AN: 36126

South Asian (SAS) AF: 0.00 AC: 0 AN: 80012

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 48270

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5654

European-Non Finnish (NFE) AF: 0.00000185 AC: 2 AN: 1079360

Other (OTH) AF: 0.00 AC: 0 AN: 58060

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

COG6-congenital disorder of glycosylation Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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	-0.76
CADD	Benign	8.3
DANN	Benign	0.86
PhyloP100		0.40
PromoterAI		0.15	Neutral

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

Other links and lift over

dbSNP: rs1442379324; hg19: chr13-40229814; COSMIC: COSV100742529; COSMIC: COSV100742529;