11-112194687-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_031938.7(BCO2):c.668C>G(p.Ala223Gly) variant causes a missense 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. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BCO2 NM_031938.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.46

Genes affected

BCO2 (HGNC:18503): (beta-carotene oxygenase 2) This gene encodes an enzyme which oxidizes carotenoids such as beta-carotene during the biosynthesis of vitamin A. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.748

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BCO2	NM_031938.7	c.668C>G	p.Ala223Gly	missense_variant	5/12	ENST00000357685.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BCO2	ENST00000357685.11	c.668C>G	p.Ala223Gly	missense_variant	5/12	1	NM_031938.7	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461030 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 726812

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 25, 2023

The c.668C>G (p.A223G) alteration is located in exon 5 (coding exon 5) of the BCO2 gene. This alteration results from a C to G substitution at nucleotide position 668, causing the alanine (A) at amino acid position 223 to be replaced by a glycine (G). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.34
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.62	D;.;.;.;.
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.96	D;.;D;D;D
M_CAP	Uncertain	0.19	D
MetaRNN	Pathogenic	0.75	D;D;D;D;D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	3.0	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Uncertain	-3.5	D;D;D;D;D
REVEL	Pathogenic	0.84
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Uncertain	0.059	T;T;T;T;T
Polyphen		0.88	P;.;.;.;.
Vest4		0.63
MutPred		0.70		Loss of stability (P = 0.0591);.;.;.;.;
MVP		0.80
MPC		0.36
ClinPred		0.99	D
GERP RS		5.1
Varity_R		0.92
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1234579244; hg19: chr11-112065410;