rs1553596645

Positions:

• chr2-218661458-G-A

Variant summary

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

The NM_001079866.2(BCS1L):​c.373G>A​(p.Asp125Asn) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BCS1L NM_001079866.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.60

Genes affected

BCS1L (HGNC:1020): (BCS1 homolog, ubiquinol-cytochrome c reductase complex chaperone) This gene encodes a homolog of the S. cerevisiae bcs1 protein which is involved in the assembly of complex III of the mitochondrial respiratory chain. The encoded protein does not contain a mitochondrial targeting sequence but experimental studies confirm that it is imported into mitochondria. Mutations in this gene are associated with mitochondrial complex III deficiency and the GRACILE syndrome. Several alternatively spliced transcripts encoding two different isoforms have been described. [provided by RefSeq, Jan 2016]

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, 0.839

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BCS1L	NM_001079866.2	c.373G>A	p.Asp125Asn	missense_variant	3/8	ENST00000359273.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BCS1L	ENST00000359273.8	c.373G>A	p.Asp125Asn	missense_variant	3/8	1	NM_001079866.2	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461880 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727242

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

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

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 22, 2017

The p.Asp125Asn variant in BCS1L has not been previously reported in individuals with hearing loss or in large population studies. Computational prediction tool s and conservation analysis do not provide strong support for or against an impa ct to the protein. In summary, the clinical significance of the p.Asp125Asn vari ant is uncertain. ACMG/AMP Criteria applied: PM2. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Uncertain	0.075	D
BayesDel_noAF	Benign	-0.13
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.67	D;D;.;D;D;D;D;D;D;D;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.94	D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.84	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.84	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-4.5	D;D;D;D;D;D;D;D;D;D;.
REVEL	Uncertain	0.59
Sift	Benign	0.074	T;T;T;T;T;T;T;T;T;T;.
Sift4G	Uncertain	0.017	D;D;T;T;T;T;T;T;T;T;.
Polyphen		0.77	.;.;.;P;P;P;P;P;P;P;.
Vest4		0.42, 0.42, 0.42, 0.39, 0.39
MutPred		0.69		Loss of helix (P = 0.028);Loss of helix (P = 0.028);.;Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);
MVP		0.99
MPC		0.88
ClinPred		0.98	D
GERP RS		5.3
Varity_R		0.61
gMVP		0.53

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: rs1553596645; hg19: chr2-219526181;