18-59431109-C-T

Variant summary

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

The NM_133459.4(CCBE1):c.*4799G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00127 in 152,230 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 0.0013 (2 hom., cov: 34)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CCBE1 NM_133459.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.262

Genes affected

CCBE1 (HGNC:29426): (collagen and calcium binding EGF domains 1) This gene is thought to function in extracellular matrix remodeling and migration. It is predominantly expressed in the ovary, but down regulated in ovarian cancer cell lines and primary carcinomas, suggesting its role as a tumour suppressor. Mutations in this gene have been associated with Hennekam lymphangiectasia-lymphedema syndrome, a generalized lymphatic dysplasia in humans. [provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00127 (194/152230) while in subpopulation AFR AF= 0.00441 (183/41528). AF 95% confidence interval is 0.00388. There are 2 homozygotes in gnomad4. There are 98 alleles in male gnomad4 subpopulation. Median coverage is 34. 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 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CCBE1	NM_133459.4	c.*4799G>A		3_prime_UTR_variant	11/11	ENST00000439986.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CCBE1	ENST00000439986.9	c.*4799G>A		3_prime_UTR_variant	11/11	1	NM_133459.4	P1
CCBE1	ENST00000649564.1	c.*4799G>A		3_prime_UTR_variant	12/12			P1
CCBE1	ENST00000650467.2	c.*4799G>A		3_prime_UTR_variant	9/9

Frequencies

GnomAD3 genomes AF: 0.00127 AC: 193 AN: 152112 Hom.: 2 Cov.: 34

Gnomad AFR AF: 0.00437

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000589

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000478

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 2 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 2

Gnomad4 NFE exome AF: 0.00

GnomAD4 genome AF: 0.00127 AC: 194 AN: 152230 Hom.: 2 Cov.: 34 AF XY: 0.00132 AC XY: 98 AN XY: 74400

Gnomad4 AFR AF: 0.00441

Gnomad4 AMR AF: 0.000588

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.000902 Hom.: 0

Bravo AF: 0.00156

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

Hennekam lymphangiectasia-lymphedema syndrome 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	-0.87
Cadd	Benign	0.78
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: rs187448235; hg19: chr18-57098341;