chr2-218662244-G-A

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PP3_StrongPP5

The NM_001079866.2(BCS1L):c.703G>A(p.Gly235Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000173 in 1,613,914 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

BCS1L
NM_001079866.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:3

Conservation

PhyloP100: 9.32

Variant links:

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]

BCS1L links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.993

PP5

Variant 2-218662244-G-A is Pathogenic according to our data. Variant chr2-218662244-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 265046.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=3, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BCS1L	NM_001079866.2 link	c.703G>A	p.Gly235Arg	missense_variant	Exon 5 of 8	ENST00000359273.8	NP_001073335.1	Q9Y276A0A024R445

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BCS1L	ENST00000359273.8 link	c.703G>A	p.Gly235Arg	missense_variant	Exon 5 of 8	1	NM_001079866.2	ENSP00000352219.3		Q9Y276

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152174

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251424

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135888

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000185

AC:

AN:

1461740

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

727188

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000198

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

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:

0.00

Alfa

AF:

0.0000564

Hom.:

Bravo

AF:

0.0000227

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.00000824

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3Uncertain:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:2

Oct 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 235 of the BCS1L protein (p.Gly235Arg). This variant is present in population databases (rs368486097, gnomAD 0.003%). This missense change has been observed in individual(s) with Bj√∂rnstad syndrome (PMID: 28322498). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 265046). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt BCS1L protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Jul 06, 2018

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The G235R variant in the BCS1L gene has been reported previously with another variant on the opposite allele (in trans) in two sisters with hearing loss and pili torti (Falco et al., 2017). The G235R variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). The G235R variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. In-silico analyses, including protein predictors and evolutionary conservation, support a deleterious effect. We interpret G235R as a likely pathogenic variant. -

Pili torti-deafness syndrome;C1864002:GRACILE syndrome;C3541471:Mitochondrial complex III deficiency nuclear type 1

Pathogenic:1

Apr 18, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Uncertain:1

Oct 08, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BCS1L c.703G>A (p.Gly235Arg) results in a non-conservative amino acid change located in the AAA+ ATPase domain of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251424 control chromosomes. c.703G>A has been reported in the literature in two sisters affected with Bjornstad Syndrome and the variant segregated with the disease (example: Falco_2016) . These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 28322498). ClinVar contains an entry for this variant (Variation ID: 265046). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Mitochondrial complex III deficiency nuclear type 1

Uncertain:1

Jul 28, 2020

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

GRACILE syndrome

Uncertain:1

Oct 18, 2017

Counsyl

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.99

BayesDel_addAF

Pathogenic

0.53

BayesDel_noAF

Pathogenic

0.61

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.92

.;D;D;D;D;D;D;D

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.99

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

1.0

D;.;.;.;.;.;.;D

M_CAP

Pathogenic

0.81

MetaRNN

Pathogenic

0.99

D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

0.92

MutationAssessor

Pathogenic

4.6

.;H;H;H;H;H;H;H

PrimateAI

Pathogenic

0.86

PROVEAN

Pathogenic

-8.0

D;D;D;D;D;D;D;D

REVEL

Pathogenic

0.97

Sift

Pathogenic

0.0

D;D;D;D;D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;D;D;D;D;D

Polyphen

1.0

.;D;D;D;D;D;D;D

Vest4

0.92, 0.92, 0.91

MutPred

0.96

.;Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);Loss of ubiquitination at K236 (P = 0.1079);

MVP

1.0

MPC

1.7

ClinPred

1.0

GERP RS

4.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.97

gMVP

0.97

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over