2-218661204-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_001079866.2(BCS1L):​c.217C>T​(p.Arg73Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000688 in 1,614,092 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R73H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000070 ( 0 hom. )

Consequence

BCS1L
NM_001079866.2 missense

Scores

6
11
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:4B:1

Conservation

PhyloP100: 3.15

Publications

11 publications found
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 Gene-Disease associations (from GenCC):
  • Bjornstad syndrome
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Orphanet, Ambry Genetics, ClinGen, G2P
  • GRACILE syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
  • Leigh syndrome
    Inheritance: AR Classification: STRONG, LIMITED Submitted by: PanelApp Australia, ClinGen
  • mitochondrial complex III deficiency nuclear type 1
    Inheritance: AR Classification: STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • mitochondrial complex III deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • renal tubulopathy-encephalopathy-liver failure syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_001079866.2

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BCS1LNM_001079866.2 linkc.217C>T p.Arg73Cys missense_variant Exon 2 of 8 ENST00000359273.8 NP_001073335.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BCS1LENST00000359273.8 linkc.217C>T p.Arg73Cys missense_variant Exon 2 of 8 1 NM_001079866.2 ENSP00000352219.3

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152198
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00173
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000163
AC:
41
AN:
251490
AF XY:
0.000118
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00308
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.000815
GnomAD4 exome
AF:
0.0000705
AC:
103
AN:
1461894
Hom.:
0
Cov.:
33
AF XY:
0.0000770
AC XY:
56
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00256
AC:
67
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000153
AC:
17
AN:
1112012
Other (OTH)
AF:
0.000232
AC:
14
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
8
16
25
33
41
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152198
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00173
AC:
6
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000304
Hom.:
0
Bravo
AF:
0.0000869
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000824
AC:
10
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1Benign:1
Mar 01, 2020
CeGaT Center for Human Genetics Tuebingen
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 30, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified with a second variant in a patient with BCS1L-related mitochondrial complex III deficiency in the published literature (PMID: 17403714); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 22310368, 23168492, 30582773, 17403714) -

GRACILE syndrome Uncertain:2
Nov 09, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Feb 13, 2024
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Pili torti-deafness syndrome Uncertain:1
Feb 21, 2023
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.45
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.65
.;D;D;D;D;D;.;D;D;D;D;.
Eigen
Uncertain
0.52
Eigen_PC
Uncertain
0.49
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Uncertain
0.93
D;.;D;.;.;.;D;.;.;.;D;D
M_CAP
Uncertain
0.27
D
MetaRNN
Uncertain
0.45
T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Uncertain
2.8
.;.;.;M;M;M;.;M;M;M;M;.
PhyloP100
3.1
PrimateAI
Uncertain
0.50
T
PROVEAN
Pathogenic
-5.3
D;D;D;D;D;D;D;D;D;D;D;.
REVEL
Pathogenic
0.84
Sift
Uncertain
0.0040
D;D;D;D;D;D;D;D;D;D;D;.
Sift4G
Uncertain
0.0040
D;D;D;D;D;D;D;D;D;D;D;.
Polyphen
1.0
.;.;.;D;D;D;.;D;D;D;D;.
Vest4
0.49, 0.48, 0.47, 0.48
MVP
1.0
MPC
1.5
ClinPred
0.57
D
GERP RS
4.6
Varity_R
0.73
gMVP
0.61
Mutation Taster
=0/100
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs140812286; hg19: chr2-219525927; COSMIC: COSV55307988; COSMIC: COSV55307988; API